HOLMES OF THE WEEK continued

[HaibaraAi7 1]

Well, we shall continue here I guess. So, anyone with any answers?

 

The case was this-

A group of four friends (Sherlock, Mycroft, Irene and John) went out to dine in a hotel on the occasion of Sherlock getting a job. When they were having dinner together, they were deciding on a nightly walk outside the hotel. However, John (Sherlock's best friend), refused as he was expecting a call from one of his mates on a reply from a job agency. The rest three decided to go anyway.

On the last minute, Sherlock too refused with an account of an upset stomach. So finally, only Mycroft (Sherlock's brother) and Irene (Sherlock's ex) went for the walk. As they were right about to leave the hotel, Irene excused herself to the bathroom and came back a bit late. Mycroft waited for her at the hotel exit gate.

 

By the time they came back, Mycroft found Sherlock shot dead in his room.

On investigation, the following points about the scene-of-crime were noticed-

• Sherlock was found shot at his right temple, in the room's toilet 
• The gun used (no silencer) was found inside a bag belonging to Mycroft

On questioning, the following facts came out

1. MYCROFT HOLMES (BIOLOGICAL SIBLING OF DECEASED)

• Was sharing the room with the deceased
• With no solid alibi, he claims to be waiting at the hotel exit gate for Irene
• When she took more than ten minutes, he called her on her mobile
• Embarrassed, Irene answered that she will be out in a minute. Mycroft heard her flush the toilet on the phone.
• He says he did not hear a gunshot. However, agrees to be in possession of a gun.
• IDENTIFIED MOTIVE: Deceased was the cause of the death of Mycroft's wife

      2. JOHN WATSON (ACQUAINTANCE OF THE DECEASED)          

• Had a private room two rooms next to the deceased's room
• Was allegedly talking to a third party individual on mobile regarding employment hunting
• The third party confirms the conversation, call log on mobile double checks.
• Claims to never have left his room. Accepts hearing gunshot but ignored it. Accepts to be in possession of a gun.
• The third party also says it heard hurried footsteps on the phone
• IDENTIFIED MOTIVE: Deceased had, at the expense of John, got his new job by bribery

 

      3. IRENE ADLER (EX-GIRLFRIEND OF DECEASED)

• Had a private room right next to the deceased's and John's room.
• Agrees with the movements described by Mycroft Holmes
• Agrees to have heard the gunshot and also heard someone rush past her door before leaving the room to catch up with Mycroft. Too had ignored the gunshot as a crashed hotel cart. Accepts to be in possession of a gun.
• IDENTIFIED MOTIVE: The relationship between the deceased and Irene ended due to the deceased unable to solve a case in time costing the life of her brother Godfrey Norton.

These accounts are sufficient to catch the murderer. With right reason, explain who the murderer is.

The hint was-

A murderer always muses on an alibi... doesn't he?

Answers will be accepted till... FRIDAY 31st MARCH 2017

[AnimeOtakuDrew 18]

Point #1. John) John left before Sherlock decided not to to go for the walk, so even though he had motive and means, he was unaware of the opportunity. Additionally, his phone call is confirmed and the person to whom he was speaking (presumably) said nothing of hearing the gunshot but acknowledged hearing footsteps. This means John was far enough away that he could hear the shot but the other party couldn't. From this, it can be deduced that John was in his room two doors down from Sherlock and on the phone as he claimed and the footsteps heard were those of the killer fleeing past John's room.

 

Point #2. Irene) Irene was staying in the room between Sherlock and John, meaning she would not have passed John's room as she fled to her own. She also could not have fled to the hotel entrance because Mycroft had already discovered the body by the time she returned.

 

Point #3. Mycroft) Mycroft shared the room with Sherlock, so he would have had the key to slip in and murder his brother. He was in possession of the murder weapon.

 

Once you have eliminated the impossible, whatever remains, however improbable, must be the truth. It is impossible for John to be the killer because the person to whom he was speaking would have heard the gunshot. It is impossible for Irene to be the killer because her fleeing footsteps would not have been heard passing John's room. Therefore, the killer is Mycroft.

 

Likely scenario: After Irene excused herself, Mycroft went to the room he and Sherlock shared and shot his brother. Fearing someone might come investigate the sound of the gunshot, he immediately fled, rushing past both Irene and John's rooms, returning to the entrance to await Irene. When Irene did not return quickly, he grew nervous (perhaps fearing she had seen him) and called her mobile to see what her reaction would be. When he got off the phone with her, he presumably decided that it would be best for him to "discover" the body as soon as possible, so he returned to the room and "found" Sherlock. (A side note, it is entirely possible that Mycroft slipped something to Sherlock during dinner to make sure he would be to ill to go for their regular walk, and possibly even to Irene to make sure she would have to excuse herself long enough for him to commit the crime. This is not definite, but it is possible.)

 

So, how did I do?

[Magic Kaito. 3]

I was doubt in Irene, for some reasons:
1) When a gun is in the possession of someone,I excluded from their suspected persons (As happens in many Detective Conan episodes haha).
2) Mycroft didn't know when Irene will come back.
3) She delayed for 10 minutes.
4) Though Mycroft hear her flush the toilet, It may be sound recorder.

~But my inference was all wrong ): !

[AnimeOtakuDrew 18]

10 hours ago, Magic Kaito. said:

I was doubt in Irene, for some reasons:
1) When a gun is in the possession of someone,I excluded from their suspected persons (As happens in many Detective Conan episodes haha).

True, but all three suspects admitted to having a gun, even though it was Mycroft found in possession of the murder weapon. Perhaps he was counting on the fact that investigators would over think things in that regard.

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2) Mycroft didn't know when Irene will come back.

Also very true, unless he slipped something to her to ensure she would take a while in the bathroom. But even if he didn't give her something, it is still possible. Mycroft would only have to wait a moment after Irene' s departure before following and going to his and Sherlock's room. He would naturally have known exactly where he kept his own gun, so he wouldn't need time to search for it. Then he ran back to the entrance immediately after committing the crime, so he would get back before her. All of these things together create enough opportunity for him to have killed his brother.

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3) She delayed for 10 minutes.

If my idea that she was given something during dinner is correct (perhaps a laxative or something similar), that would have been expected. Even if that is not the case, it is entirely possible that a bathroom break could take that long. A lady wouldn't go into detail about just what she needed to do in the bathroom, but she may have wanted to touch up her makeup or any number of other things while she was gone. And that is looking beyond the obvious idea, that whatever upset Sherlock's stomach at dinner might have had some effect on Irene as well and given her "the runs."

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4) Though Mycroft hear her flush the toilet, It may be sound recorder.

Since Sherlock was found in a bathroom, it could theoretically be the toilet in Sherlock's bathroom that she flushed for Mycroft to hear, but I don't believe this. If Irene had killed Sherlock, depending on when the call from Mycroft was, he might have heard something over the phone. She would naturally have fled immediately after committing the crime, so the question then becomes, where could she go? Not the entrance, because she didn't rejoin Mycroft until after the body was discovered. Not her room, because her footsteps would not have been heard from John's room. The information given doesn't propose any other alternatives, like a service closet or side entrance. For those reasons, it just doesn't seem to fit that it was Irene. If it was Mycroft, however, he initiated the call to Irene, so he was able to make sure it was at a time when she would hear nothing suspicious. The fact that the fleeing footsteps were heard in both Irene and John's rooms then makes sense. I also find it suspicious that Mycroft found the body before Irene returned if he's not the killer. Why would he go back to his room if he's waiting for her? It clearly had to be after he talked to her on the phone, otherwise he would have mentioned then that he found his brother dead. But, when he was on the phone with her, Irene said she would be out in a minute and he heard a toilet flush, indicating she would be there momentarily. Likewise, if he suddenly needed to use the restroom, he would have mentioned that to her on the phone so she wouldn't be surprised by his absence when she returned. It just makes no sense for him to randomly decide at that point to revisit his room when he knew she was coming soon, unless he is the killer. Maybe he got nervous that he left some damning piece of evidence and wanted to go hide or destroy it. Who knows. But Mycroft as the killer is the only way I see ALL of the pieces fitting together. The only other possibility I see is that Mycroft and Irene were working together, but even that doesn't completely fit because they would then acted as each other's alibis rather than leaving glaring holes in their timelines when either had the opportunity to commit the crime.

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~But my inference was all wrong ): !

(WrongEnIK)

Well, I started to think that way at first as well, so it is understandable. And while there is enough information there to ultimately figure it out, the information is incomplete. Real police reports would contain times. What was the TOD? What time did John's call start and end? What time did Sherlock leave Irene and Mycroft? What time did Irene leave? What time did Irene and John hear the shot? What time did Irene and the person to whom John was speaking hear the footsteps? What time did Mycroft call Irene? And finally, what time did Mycroft find the body? That information would all have been in the reports, but we didn't get it. I can only guess such pertinent information was left out because it would then make the solution TOO obvious. That was my deductive process. I still admit I could be wrong, but that is the only way it makes sense to me. We will have to wait for the the original poster to confirm or deny my reasoning to know for sure, and since the post says solutions will be accepted until the 31st, I'm guessing confirmation won't come until then.

[Detective Magic 0]

From my point of view, you are making a big mistake. You are assuming Irene didn't see Mycroft after she went to the toilet. But accorgding to the case description:

On 29.03.2017 at 10:09 AM, HaibaraAi7 said:

So finally, only Mycroft (Sherlock's brother) and Irene (Sherlock's ex) went for the walk. As they were right about to leave the hotel, Irene excused herself to the bathroom and came back a bit late. Mycroft waited for her at the hotel exit gate.

 

By the time they came back, Mycroft found Sherlock shot dead in his room.

If Irene didn't see Mycroft till he discovered the body (from your deduction after calling Irene), then who would have come back and from where? And where does the hint about alibi go?

Of course I could have misunderstood your deductions and if so, then I'm sorry.

My idea also has a lot of inconsistencies, but here you go. Warning! - It may be a bit chaotic

Mycroft certainly isn't the culprit. All evidence is against him - Mycroft found the body, the gun was in Mycroft's bag, Mycroft was outside so he had no alibi([and that's the point, if he was the culprit he wolud have made himself a solid one) he had a motive (everyone had but still) - so it would be too easy. Also everybody knew he would be the first one to go into his and Sherlock's room.

As everyone had a gun, the culprit could have used his own and then swap it with Mycroft's.

When all four were eating dinner, Irene or John slipped something to Sherlock's meal, so he would later stay in his room.

Ver. 1

John decided not to go on a walk, because he knew how much time would it take for the pill (or whatever it was) to start working. He then called his friend who knew about John's motive. Friend was an accomplice and he helped John estabilish an alibi, so he lied to the police about the conversation. He left the phone working and went to Sherlock's room. He was his best friend so Sherlock let him in. He then shot him in the bathroom, switched his gun with Mycroft's (that was also his room so the bag and his gun wouldn't be hard to find) and left. He passed Irene's door, not knowing she was in her room and went to his room. Of course when the police came, he lied about the conversation and told he heard some footsteps to blame someone else. His friend as they agreed, confirmed his story.

Ver. 2

John decided to stay. Irene didn't know when the pill would start working, so when Sherlock went back to the hotel, she saw her chance. She excused herself telling she must go to the toilet. She then went to Sherlock and he let her in (she was his ex). She then shot Sherlock and waited some time. She predicted Mycroft would be worried and after 10 minutes he called. She pretended to be embarassed and flushed the toilet. (And the fact that she left him waiting could be done so he wouldn't have an alibi. Then she swapped guns and hurried downstairs. John heard her hurried footsteps. After the police came she lied about somebody running past her door to blame someone else. She also told her story about mistaking the gunshot with crashing hotel cart. Of course she also had a motive.

They both also could have used Mycroft's gun from the beginning and then they hid it in his bag. But the fact that Mycroft would call Irene is very unstable, just like the fact that John heard her footsteps (he was too far).

As you can see, John seems way better than Irene, but I still consider version 2 as possible. I agree that the description could be more detailed, but still I'm amazed that you thought of this in such a short time.

[AnimeOtakuDrew 18]

What is hanging me up is the wording, "By the time they came back, Mycroft found Sherlock shot dead in his room." If this was referring to the walk, it makes things confusing. Mycroft obviously couldn't find Sherlock's body in his room while he is out on a walk, so there is clearly a mistake in the grammar. That leaves only conjecture as to what it should have been. The only possibilities that fit the context are, "by the time she came back" (referring to Irene returning from the restroom) or, "when they came back" (meaning Mycroft discovered the body upon their return rather than "by the time " of it). With this typo, the former is more likely than the latter because there I less change to the sentence structure (replacing only one word rather than three). That is why I made my deductions based on the idea that Mycroft found the body by the time Irene returned to join him. If the purpose of the text was different, then my deductions would be different. If the original poster wants to clarify/correct that, I will rethink my deductions. But with the the typo leaving two possible interpretations which lead along two very different lines of reasoning, I will stick to what I've got.

[Ayuna Yume 6]

Hey, since the real poster haven't commented anything, I think that the culprit is John and here's my 'deduction' haha

Well, since the hint is 'muses up 'alibi', it is likely that John, the only person with a seemingly solid alibi that did this. The reason that I suspect this is, why didn't John hear the footsteps that the third party he was talking to in the phone did? I'm assuming that he didn't hear the footsteps cause anyone would surely mention such suspicious thing to the police had they heard it. So here's my reasoning :

  

John might've slipped some kind of pill into the victim's dinner, everyone had the opportunity to do so after all. Then, he excused himself back to his room and called his friend. After the pill had finally started to take effect, he went to the victim's room. I'm just guessing but he might've asked to meet the victim beforehand so that he won't lock the door. They DO seem like having a lot of stuff to talk about ( pardon my grammar here). Then, he shot the victim with Mycroft's gun before quickly hurrying back to his room, not noticing the sounds of his footsteps, all while still on the phone with his friend... Their rooms are relatively close so I don't think he would've been catching his breath...

 

I DO admit that my 'reasoning' sounds a LOT impossible... I wish the poster will just post the answer soon.... Correct me if I'm wrong, though

[AnimeOtakuDrew 18]

There is only one flaw in your reasoning, Ayuna-chan. If John took his phone with him when he went to commit the murder, the person to whom he was speaking would have heard the gunshot. In the other hand, if John left the phone behind while going to commit the crime, the other person would have been aware John was away from it. As the person to whom John was speaking reported neither hearing the gunshot not John leaving the phone, the only way John could have committed the crime is if the person on the phone was in on it.

 

As for the hint about musing on an alibi, that doesn't necessarily mean that the killer has an alibi, only that he/she speaks of it. Now consider that the only suspect whose reports included the word "alibi" is Mycroft.

 

Anyways, we may never know the solution as the original poster seems to have abandoned the topic.

[HaibaraAi7 1]

On 29/03/2017 at 9:47 PM, AnimeOtakuDrew said:

Point #1. John) John left before Sherlock decided not to to go for the walk, so even though he had motive and means, he was unaware of the opportunity. Additionally, his phone call is confirmed and the person to whom he was speaking (presumably) said nothing of hearing the gunshot but acknowledged hearing footsteps. This means John was far enough away that he could hear the shot but the other party couldn't. From this, it can be deduced that John was in his room two doors down from Sherlock and on the phone as he claimed and the footsteps heard were those of the killer fleeing past John's room.

 

Point #2. Irene) Irene was staying in the room between Sherlock and John, meaning she would not have passed John's room as she fled to her own. She also could not have fled to the hotel entrance because Mycroft had already discovered the body by the time she returned.

 

Point #3. Mycroft) Mycroft shared the room with Sherlock, so he would have had the key to slip in and murder his brother. He was in possession of the murder weapon.

 

Once you have eliminated the impossible, whatever remains, however improbable, must be the truth. It is impossible for John to be the killer because the person to whom he was speaking would have heard the gunshot. It is impossible for Irene to be the killer because her fleeing footsteps would not have been heard passing John's room. Therefore, the killer is Mycroft.

 

Likely scenario: After Irene excused herself, Mycroft went to the room he and Sherlock shared and shot his brother. Fearing someone might come investigate the sound of the gunshot, he immediately fled, rushing past both Irene and John's rooms, returning to the entrance to await Irene. When Irene did not return quickly, he grew nervous (perhaps fearing she had seen him) and called her mobile to see what her reaction would be. When he got off the phone with her, he presumably decided that it would be best for him to "discover" the body as soon as possible, so he returned to the room and "found" Sherlock. (A side note, it is entirely possible that Mycroft slipped something to Sherlock during dinner to make sure he would be to ill to go for their regular walk, and possibly even to Irene to make sure she would have to excuse herself long enough for him to commit the crime. This is not definite, but it is possible.)

 

So, how did I do?

 

Point#2 is at fault. Irene returned before the body was discovered

 

[AnimeOtakuDrew 18]

 

12 hours ago, HaibaraAi7 said:

Point#2 is at fault. Irene returned before the body was 

Okay, now that the original poster has clarified that the intended meaning was that Mycroft found the body after returning from the walk with Irene, that changes my line of reasoning.

 

Point #1 is still valid. John was on the phone at the time of the murder, and the person to whom he was speaking did not hear the gunshot nor did he report that John left the phone, so it cannot be John.

 

Point #3 is also still valid. Mycroft did have the key to the room and the gun was found in his possession. Also, if he surreptitiously returned to the room immediately once Irene was out of sight, he would have been able to commit the crime and return to the entrance before Irene's return. The hint about the killer musing on an alibi is also suspect, considering that to muse could mean a few different things, along with the thought that Mycroft's statement is the only one that contains the word alibi. He would have mused on the fact that his only alibi is that he was at the entrance waiting for Irene.

 

However, now that we know Irene had returned before the body was discovered, she becomes much more suspicious. Since we do not have times listed for anything, we don't know how long before Irene's return it was before the shot and the footsteps were heard. For that reason, it is possible that Irene could have committed the crime just prior to returning. While her statement does not contain the word alibi, she too mused on what she claimed to have been doing at the time of the crime.

 

There are two primary roadblocks in the way of making a definitive deduction in this case. First is the absence of times; something that real police reports would have made certain to list, at least in estimation. Estimated time of death, estimated times the witnesses heard the shot and footsteps, the exact time John's call started and ended, and estimated time that Irene returned to the entrance. This is information that would be present in a real case, and is extremely relevant (even important) to accurately identifying the perpetrator. The second roadblock is that we are not given complete information. A major hang-up for each suspect is what knowledge they would have had regarding the movements of the victim and each other. With the information given, John had no way of knowing that Sherlock wasn't walking with Irene and Mycroft, Mycroft had no way of knowing that Irene would be delayed in the toilet, and nobody had a way of knowing that Sherlock would be too ill to go for the walk thus granting the opportunity for this murder in the first place. The obvious answer is that Sherlock was given something to ensure he would be so ill as to bow out of the evening walk. This could have been anything from a heavy laxative to some form of poison. In a real case, a tox screen would have been run on the victim and investigators would know if any such chemicals were present in Sherlock's system. As with the times, this is very important information. John still couldn't have committed the crime because he was on the phone. If Sherlock was drugged by Mycroft to ensure he would bow out of the walk, it is just as likely Irene was given a smaller dose to ensure she would be delayed in the toilet thus granting him enough time to murder his brother. However, because there is no information given on a tox screen, we must take it at face value that neither Sherlock nor Irene were drugged in any way, meaning the murder was a crime of opportunity. In light of that, Mycroft's guilt becomes less likely. For all he knew, Irene would only be in her room for a very brief moment, so he could not be certain that he would have time to commit the crime and return to the entrance before she emerged from her room. With that in mind, the only possible suspect left is Irene, therefore, she must be the killer.

 

Likely scenario: Before departing for her walk with Mycroft, Irene excuses herself with a lie about needing to visit the toilet. She instead goes to Sherlock's room. Since she is his ex, it would not be difficult for her to convince him to grant her entry (mentioning the possibility of getting back together, suggesting they have a quick romp while Mycroft is out, etc.). Because Sherlock had already made it clear he was suffering from an upset stomach, Irene could be fairly certain that he would indeed need to use the toilet soon, so she stalled until then. The likely reason she was delayed before returning to Mycroft at the entrance was because he took longer than she expected before doing so. When Sherlock finally went to the toilet, Irene quickly found Mycroft's gun and she entered the toilet and shot Sherlock. It is probable that Mycroft's call came in at this time, which she answered to explain that she would return momentarily, then flushed Sherlock's toilet for effect. She then quickly stuffed the gun into a bag belonging to Mycroft and rushed toward the entrance. These were the running footsteps heard by John's caller. Later, when questioned by the police, Irene would muse on the fact that she had been in her own toilet when she heard the shot and claim to also have heard footsteps to add plausibility.

 

That seems the most likely possibility with the scant information given. If the original poster wishes to expand the case information to include times and the results of a tox screen as a real case file would contain, I may revise my deduction yet again, but for the moment I must contend that Irene was the killer.

[HaibaraAi7 1]

On 29/03/2017 at 9:47 PM, AnimeOtakuDrew said:

Before departing for her walk with Mycroft, Irene excuses herself with a lie about needing to visit the toilet. She instead goes to Sherlock's room. Since she is his ex, it would not be difficult for her to convince him to grant her entry (mentioning the possibility of getting back together, suggesting they have a quick romp while Mycroft is out, etc.). Because Sherlock had already made it clear he was suffering from an upset stomach, Irene could be fairly certain that he would indeed need to use the toilet soon, so she stalled until then. The likely reason she was delayed before returning to Mycroft at the entrance was because he took longer than she expected before doing so. When Sherlock finally went to the toilet, Irene quickly found Mycroft's gun and she entered the toilet and shot Sherlock. It is probable that Mycroft's call came in at this time, which she answered to explain that she would return momentarily, then flushed Sherlock's toilet for effect. She then quickly stuffed the gun into a bag belonging to Mycroft and rushed toward the entrance. These were the running footsteps heard by John's caller. Later, when questioned by the police, Irene would muse on the fact that she had been in her own toilet when she heard the shot and claim to also have heard footsteps to add plausibility.

 

 

 

1

 

BRILLIANT! That is EXACTLY how it happened. Drew-sama is the Holmes of the (till the next time).

Irene Adler would NOT be too happy, but at least the world is a better place.

Although this would not have been deductible, Irene was 'checking' on Sherlock if he were okay. The upset stomach caused vomiting, Irene helped Sherlock get to the bathroom so he could do his job. When Mycroft called, she was flushing down Sherlock's vomit! After the call, Irene shot Sherlock, cleaned herself of any gunpowder residues (she was after all in a bathroom), switched her gun with Mycroft's, and came prancing back to the exit gate. 

 

I apologise about the ambiguity of Irene's return I had made earlier. But since Drew-sama answered first post the clarification, he has to be crowned.

 

[HaibaraAi7 1]

On 30/03/2017 at 8:49 AM, AnimeOtakuDrew said:

Since Sherlock was found in a bathroom, it could theoretically be the toilet in Sherlock's bathroom that she flushed for Mycroft to hear, but I don't believe this.

 

 

Funny how initially Drew-sama discarded the correct theory, only come out with the correct one later on again 

Well, I hope this case was interesting enough for everyone...

Anyhow, who's up to make the next case?

[AnimeOtakuDrew 18]

1 hour ago, HaibaraAi7 said:

Funny how initially Drew-sama discarded the correct theory, only come out with the correct one later on again 

I only dismissed it initially because I misinterpreted the sequence of events. Like I said before, the typo of "by the time they came back." As I explained before, when it comes to typographical errors, figuring out the intended meaning out of the possible variations is usually as simple as finding the solution that least changes the structure of the sentence. "By the time she came back" entails less structural change than "when they came back," so that was how I interpreted it, and that is what I based my initial deduction on. Had the verbiage been more clear, I would not have so easily dismissed the possibility of Irene.

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Well, I hope this case was interesting enough for everyone...

Indeed it was. I enjoy using my brain.

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Anyhow, who's up to make the next case?

I wouldn't mind coming up with one, but I would need a day or two to put it together. If anyone has one ready in the meantime, by all means, go ahead.

 

I should also note that Magic Kaito. made a case against Irene long before I did. He may have been incorrect on a couple details, such as suggesting that the sound of the flushing toilet was a recording device, but he had correctly identified the killer. The only thing he didn't do is formally declare it was her. He merely stated that he was suspicious of her.

[Detective II 0]

ME: Let me reconstruct how does the culprit do it.
When they were having dinner together, the culprit putted a drug from Sherlock's drink that will make Sherlock's stomach ache.
Then the culprit and Mycroft went for the walk, as they were right about to leave the hotel, the culprit excused herself to the bathroom.
and the culprit came to Sherlock's room to kill him while Sherlock is using the toilet, the culprit knock the door at the toilet,
then Sherlock open the door without knowing that he's being targetted by the culprit, then the culprit point the gun at his right temple and shot him,
then came to the hotel exit gate so that her alibi would work, but she don't know that coming late would make him more suspicious.
So, yes the culprit is IRENE ADLER.
Mycroft Holmes claims to be waiting at the hotel exit gate, but let's see who can confirm it, who?
GUARD, the GUARD is always guarding the hotel exit gate, Mycroft Holmes might have seen him, PROBABLY.
John Watson was allegedly talking to a third party individual on mobile regarding employment hunting, who can confirm it?
The one who he was talking with on mobile, he can confirm his alibi and also if he was near the victim when he was talking to him, because if he killed the victim, he will hear more sound than being in his room.

AND NOW, WHERE'S YOUR ALIBI, YOU TAKING THE BATHROOM, IRENE ADLER?!

 

IRENE ADLER: Yes, I don't have an alibi! But that doesn't mean I am the culprit. 
HAHAHAHA! Yes, it is an excellent deductive reasoning, but where's your proof?!!

 

ME: As I can smell, a gunpowder is in your body, if it is proven that the gunpowder is from the gun that is used to kill Sherlock,
then it'll also be a proof that you kill SHERLOCK, IRENE ADLER!
 

Edited: I guess this one is over, okay let me give another one.

It was 8:35 A.M. and Cynthia Peck was not only in a bad mood but late for work as well, which was most unusual for her. Not only was she late, but rain had been coming down in a torrential downpour since 7:13. She knew it was 7:13 because that is what the digital clock in her automobile reflected as the first thick raindrops splattered her windshield. As she entered the Ames building, she cursed silently that her oversized umbrella had done a poor job of keeping her dry. But, today, it was probably good that she was late, for it could possibly be herself that her administrative assistant, Megan Brewer, found dead on the floor of her spacious office.

Cynthia Peck was 37 years old and a vice president of the Ames Marketing Company. She did not become a company vice president by being weak or faint hearted. She knew something was wrong as she exited the sixth floor elevator and met several uniformed police officers waiting for her to arrive. Before the officers had a chance to say anything to her, she asked, “What is going on?”

Detective Sergeant Kyle Whitmore answered, “Are you Cynthia Peck?”

“Yes,’ she replied and asked again, “What’s going on?”

“There is a dead man in your office. Your assistant, Ms. Brewer, found him this morning. Identification in his wallet shows him to be Mr. Trent Willis. Do you know him?”

Cynthia showed no emotion as she answered, “Yes, we had a meeting in my office scheduled for this morning. What happened?”

“He was murdered,” the detective answered, watching Cynthia carefully, and added, “he has a letter opener in his chest. The only belongings we found were his cell phone and briefcase.” The detective did not share with her the fact that the state of her office indicated the powerfully built Willis, whose driver’s license showed him to be 35 years old, put up a violent but futile struggle with his attacker.

Cynthia now felt a slight dizziness. Small beads of perspiration broke out upon her high forehead as she asked, without visible emotion, “Who did it?”

“We don’t know yet,” Sergeant Whitmore answered, noticing the wetness on Cynthia’s clothing. He pointed towards the end of the hall and said, “Please join us in the conference room after taking a moment to dry off.”

“Thank you,” she gratefully replied. Upon entering the conference room, Cynthia saw that her assistant, Megan Brewer, was already seated along with her boss, company president Steve Ledbetter and a member of her marketing team, Josh Kesler. She quickly took a seat and noted that a uniformed policeman stood at the door. Anyone wishing to enter or exit the room would have to do so through the officer.

The four Ames employees looked expectantly at Sergeant Whitmore. Whitmore silently noted to himself that the Ames employees, with the exception of Steve Ledbetter, appeared to be between 35-40 years old and in good physical condition. President Ledbetter was the exception, being 58 years old and at least 50 pounds overweight.

He began to speak, “Ms. Brewer found the victim at 7:51 this morning. Mr. Willis, as you know, Ms. Peck, had an 8:15 appointment to see you. Ms. Brewer claims not to know how he got to the sixth floor and into the office. I know that I do not need to tell you that the stairways are locked and a pass code is needed to exit the elevator on the sixth floor. Now, Ms. Peck and Ms. Brewer are the only persons with a passkey into Ms. Peck’s office, but Ms. Brewer informs us that she left her passkey on her outer office desk for a few moments while in the break room getting a cup of coffee. Security tells us that four persons accessed the sixth floor before 7:51.” Whitmore stopped for a moment to catch his breath and, with a sweeping motion of his hand, added, “And those persons are all of you. Before anyone asks, records show Ms. Peck exited the elevator at 6:45, a little over an hour before Mr. Trent was discovered.”

“It’s true, Sergeant. Stupidly, I left the signed contract I was to give to Mr. Willis at home. I had to return home and get it.”

The sergeant looked at Cynthia and said, “OK, for now. What security shows is that Ms. Peck arrived at 6:45, and Ms. Brewer was next at 6:59. At 7:25, Mr. Kesler arrived. Mr. Ledbetter was last to arrive at 7:40.” Sgt. Whitmore paused and looked at each of them in turn before adding, “It’s highly unlikely that somebody hid overnight on the sixth floor, but we’re checking security cameras as I speak. What is much more likely is that one of you murdered Trent Willis.”

Megan felt faint and began to weep. Softly, Sgt. Whitmore said to her, “I’m sorry, Ms. Brewer, this is unpleasant but necessary.

Steve Ledbetter asked, “Why not check the cameras to see when Mr. Willis entered?”

“Because lightning knocked them out early this morning, before the rains hit,” was the sergeant’s reply. Turning to Cynthia, he said, “Let’s begin with you, Ms. Peck. You first arrived at 6:45. Did you enter your office?”

“Yes. It was then that I discovered that I left the contract at home. I left to retrieve it.”

“Security shows you left the sixth floor at 6:49,” Whitmore noted,

“That’s right,” Cynthia answered.

“So it took you an hour and 46 minutes to get back here?” Whitmore asked.

“Right again. The rain hit at 7:13 by my car radio and traffic crawled to a stop. I was in my car the entire time, except for the short time I was in my apartment retrieving the contract.” Cynthia thought for a moment as Whitmore’s eyes bored into her and then added, “I made several cell phone calls from my car, one of them around 7:10 to the newspaper delivery service, one to my husband’s office around 7:35 and another just after 8:00 to my doctor’s office. Telephone company records will show my cell phone to be a long way from here between shortly after leaving until after 8:15 or so.” As she said this, she handed Sgt. Whitmore her cell phone.

Whitmore thanked her and turned to Cynthia’s assistant, Megan Brewer, who had composed herself. He stated, “You exited the elevator at 6:59. Did you notice anything out of the ordinary when you arrived?”

“Nothing. I noticed the lightning outside the windows but that is all.”

Thinking for a moment, he asked, “Did Ms. Peck call you at anytime after leaving to return home?

“No, but that is not unusual. She only calls when she needs to. This morning, she sent an email before leaving, explaining the situation and asking me to make Mr. Willis comfortable.”

Whitmore turned to Josh Kesler and asked, “What about you? You got here at 7:25. Did you see or hear anything out of the ordinary?”

“No,” was his response.

Did you make any calls on your cell phone or from the office; anything that can prove you are not the killer?”

Nervously, Josh replied, “No, nothing.”

Whitmore thought for a long moment, and then asked Steve Ledbetter. “Do you have a raincoat?”

“Yes, but I do not have it with me. As president of the company, I have a car and driver at my disposal. Maurice always lets me out right at the front door so I never wear a coat.”

Turning back to Josh Kesler, “And you? Do you have a raincoat?”

Josh was puzzled but answered, “No, but I have an umbrella. If you want to see it, it’s drying in my office.”

Sergeant Whitmore had seen a lot in his 12 years as a homicide investigator, but never anything as bizarre as this. But a High School in his uniform shows up and pointing his finger to the murderer, he said to the officer guarding the door, “Arrest this person for second degree murder.”

“I've overheard the case, and have solved it myself.” said the High School Student.
So how does the High School Student knew it?