Mary Sera

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Mary Sera
Profile
Japanese name:	メアリー 世良 (Mearī Sera)
Age:	Looks approximately middle school aged according to Conan Real age is 53
Gender:	Female
Relatives:	Tsutomu Akai (husband, deceased) Shuichi Akai (first son) Shukichi Haneda (second son) Masumi Sera (daughter) Elena Miyano (younger sister, deceased) Atsushi Miyano (younger brother-in-law, deceased) Akemi Miyano (niece, deceased) Shiho Miyano (niece)
Occupation:	MI6 Agent Housewife
Status:	Alive (shrunk) Dead (for the Black Organization)
Nicknames:	Sister from outside the domain
Statistics
First appearance:	Manga: File 875 Anime: Episode 756
Appearances:	Mary Appearances
Cases solved:	1
Keyhole number:	Volume 83
Actors
Japanese voice:	Atsuko Tanaka

Mary Sera (メアリー 世良 ,Mearī Sera), also known by her marriage name as Mary Akai (赤井 メアリー ,Akai Mearī) appears as a middle-school age girl with blonde hair who has been hiding in various hotels in Tokyo with Masumi Sera. Despite her appearance, she is actually a middle-aged woman; she is the wife of Tsutomu Akai, and the mother of Shuichi Akai, Shukichi Haneda, and Masumi Sera. She is a member of the British Secret Intelligence Service, often known as MI6.

Background

Masumi thinking back to her mother's transformation

Mary Sera's full background is currently unknown, She met and married Tsutomu Akai, and bore three children, Shuichi, Shukichi, and Masumi. Her husband left at some point before Masumi was born, to investigate the double murder of Kohji Haneda and Amanda Hughes, which got him tangled with the Black Organization.

Later on, Mary learned that her husband was apparently roaming London and immediately travelled there, taking Masumi along as added insurance. Leaving her daughter in their hotel room, she left to meet Tsutomu at their favorite meeting place at Vauxhall Bridge. There she was trapped and forced to ingest the APTX by Vermouth, causing her age to be regressed and return to Masumi hours later in the body of a middle-school child.

Right after her return, Mary and Sera watched a recording of a TV broadcast about Conan Edogawa's involvement in the attempted blackmail of Minerva Glass and immediately recognized him as Shinichi Kudo, whom they had encountered ten years ago. She returned to Japan with Masumi in order to find out about the existence of an antidote to the APTX, which Shinichi apparently has access to, using Masumi as a proxy for her investigations. She also has expressed an interest in the death of Kohji Haneda and the identity of the missing bodyguard Asaka.

Personality

Mary seems very mature and direct, especially when speaking to Masumi. She seems hesitant to trust others at the moment and is being extremely cautious about who knows about her. Currently because of her cautiousness, she and Masumi have been moving from one hotel to another to keep their location hidden.

She is proud of her British heritage.

Like her eldest son she also seems to be clumsy at recognizing the motives behind the feelings of others and how to interact positively with others. In dealing with her children, Mary seems to be strict and cold, treating her children more like coworkers than a family. Shukichi seemed to be more nurturing to Masumi than her mom. When Mary was 10 years younger, she came to physical blows with her eldest son, Shuichi, since he lied to her about his reasons to study in the USA and planned to join the FBI and investigate her husbands' incident. They both went as far as attacking each other's faces, leaving black eyes. She also thought Shuichi, who is a rather cold person as well, would make a good replacement father figure for Masumi and Shukichi. However, soon after she realized that Shuichi was driven by the same sense of curiosity as his father and he would go his own way. To her daughter Masumi, she acts secretively by hiding a lot of important information from Masumi, such as turning off the TV when Shuukichi shogi match was shown, and possibly some other whereabouts of the Black Organization and the Akai family overall. Her continued mistrust of Conan is another example of her general denseness at understanding others, since it is long past the point where she should be able to tell that Conan's motives and pursuit of justice are genuine.

But she does express joy at Shukichi's victory for becoming the seven-crowned Shogi master. It indicates that she does care for her children. Additionally, when Mary easily sees through Vermouth's disguise of Tsutomu, she appears genuinely distraught at the fact that her husband is apparently dead and even cries and didn't seem to be concerned about her fate as long as Masumi remains save, showing regardless of her tough attitude, she truly cares for her family. The apparent death of Tsutomu may have contributed to her hardened personality.

Appearance

Mary's two different eye patterns.

Mary is a girl of middle school age (12-15) with blonde, curly, neck length hair. The child has eyes similar to those of Masumi Sera and Shuichi Akai. In her appearance in File 877, she was shown wearing a high-neck pleated top, hoodie jacket, and hat. Like all the other manga characters, the color of her eyes is supposed to be blue, as seen in the keyhole of manga volume 83. She had a well-endowed adult body when young Shinichi and Ran met the Akai family on a beach in the past.

In her varying appearances, Mary's eyes have been drawn slightly differently. In her original and current chapter appearances she seems to have an extra lash on the top of her eye, where as in the Pool case and Conan's comparison of her and Haibara's eyes in the Department store case she does not have that extra lash.

Skills

Mary's hiding skills.

Mary seems to know about several types of wire taps. When she and Masumi find Conan's wire tap in their room, she says that she hasn't seen that type before. She also describes the components of it such as its battery life and performance. She spoke in a similar fashion about Conan's voice changer after she gets a chance to use it herself.

She has demonstrated the ability to hang from a balcony by a thin rope/wire and hug the wall like a ninja. She has the strength to vault back up on to the balcony, much like Vermouth did in the New York case.

10 years ago she already had the ability to fight well enough that she landed a "knife-hand strike" to her son Shuichi's face, who at the time had already been practicing Jeet Kune Do. In the present, even with her small body, she was able to take down a fully grown man by herself. Conan described the damage as "a copped blow to a vital spot, similar to the techniques used by the secret service".

Appellations

Picture	Name	What they call Mary	What Mary calls them
	Tsutomu Akai	-	Tsutomu-san Husband (Shujin) Ano hito (literally "that person", but the intended meaning is "husband")
	Shuichi Akai	Mom (Kāsan) Mother (Haha)	Shuichi
	Subaru Okiya	-	Brat of the FBI (FBI no kozo)
	Shukichi Haneda	Mom (Kāsan) Mom Mary (Mary-kāsan)	Shukichi
	Masumi Sera	Mama The little sister from outside the domain (ryōiki-gai no imōto)	Masumi
	Kohji Haneda	-	Kohji Haneda Kohji

Picture	Name	What they call Mary	What Mary calls them
	Vermouth	Mary Akai	Witch of a thousand faces (sen no kao wo motsu majo)

Picture	Name	What they call Mary	What Mary calls them
	Conan Edogawa	Mary That girl (ano shōjo) The little sister from outside the domain (ryōiki-gai no imōto)	Edogawa Conan This boy (kono shōnen)
	Ran Mouri	That girl (ano ko)	-

Plot overview

The Red Woman Murder Case (Manga: 875, Anime: 756)

Mary on Masumi's phone.

Masumi asks Conan to find her cellphone by calling it with his. When he does he notices the call background screen is a child with eye bags similar to those of Shuichi Akai and Masumi Sera. He remarks that the girl looks similar to Masumi. Earlier in the case she only mentioned having two brothers; a mother; and a father, so Conan suspects Masumi was intentionally trying to show him the child for some reason.

Romance Novelist Murder Case (Manga: 876-878, Anime: 759-760)

Mary and Masumi.

When Ran, Sonoko, and Conan visit Masumi's apartment, Mary is shown opening Masumi's door as Conan, Masumi, Sonoko, and Ran rush to investigate a crime. It is implied she was hiding in Masumi's bedroom while the other three were in the dining area because Masumi asks Conan not to enter her bedroom. Mary later goes downstairs to the scene of the crime where she is seen by Conan. At some point off screen Conan leaves behind a bug in Masumi's room. After the case is solved, Mary is shown examining Conan's bug along with Masumi, who had found it and crushed it. Mary comments on the quality of the performance of the bug itself and that she has never seen one like it. When Masumi asks if Mary has taken a liking to Conan she says that it is still early to trust Conan, and asks Masumi to introduce her as "the little sister from outside the domain (領域外の妹 ,ryōiki-gai no imōto)", should Conan question her in the future.

Shogi Tournament (Manga: 899-902, Anime: 785-786)

Mary and Masumi in the bedroom.

Mary is interested in Shukichi's shogi match. When Masumi returns to the hotel room in the middle of the case while Mary is napping, she turns on the TV and sees the shogi match. Later after the case is solved, Masumi enters the room for a second time to see Mary turning off the TV. Presumably she saw the end of the match and was happy at Shukichi's victory, as was Subaru Okiya, whose identity was revealed in the case before this one, to be Shuichi.

Poolside Case (Manga: 903-905, Anime: 787-788)

Ran sees Masumi and Mary.

Mary is waiting for Conan to visit her and Masumi in their hotel room. She expresses her still-lingering concern of trusting Conan, even though she thinks he is bright enough. Mary does comment that if anything were to go wrong they would have to move hotels again. Her talk with him alone is put on hold, however, because Ran and Sonoko have invited themselves in accompanying Conan in order to enjoy the hotel's pool. As Conan, Ran, and Sonoko head back home after the case is solved, Ran turns around and sees Masumi talking to her. Ran gets the feeling that she has seen that child before.

A Killer in Ramen Ogura (Manga: 928-930, Anime: 827-828)

Conan with the handkerchief.

Masumi Sera is at Ramen Ogura with Conan, Sonoko and Ran. Katsumasa Ogura asks Masumi (mistakenly calling her "Mari") if she's going to take the same food to her apartment again. Conan implies that Masumi could be giving food to someone she's letting stay in her apartment, making a clear reference to Mary, but she jokes saying that it's for her secret boyfriend. At the end of the case it is revealed that Ogura had found a handkerchief that Masumi had left behind that said "Mary" on it in English. Ogura had confused the English name with the Japanese name "Mari". Conan believes that the handkerchief may be related to the child as well.

Department Store Stabbing Case (Manga: 939-941, Anime: 843-844)

Conan makes a connection between Mary and Haibara due to some remaining makeup.

Conan thinks about Mary, "the little sister from outside the domain looks a lot like Sera, no wait, more than that girl resembling Sera..." (領域外の妹と名乗る… 世良によく似た… いや…　あの子世良というより…‥ ). Conan also thinks to himself that the child's name is probably Mary. At the end of the case Haibara tried to wipe some of the makeup off of her face in the bathroom, but she missed some just below her left eye. The left over makeup made it look like she had the same eye bags as Shuichi, Masumi, and Mary. This causes Conan to make a connection between her and Mary.

Soul Detective Murder Case (Manga: 951-953, Anime: 863-864)

"Mama?!"

Kogoro is put in contact with a Soul Detective who wishes to reveal some information about the Kohji Haneda case. When Conan and Kogoro go to meet with him at the hotel, they find him dead and that Masumi and Mary are presently staying in the next room. During the investigation Conan runs into Masumi's hotel room and checks the balcony as that is the only place a person would hide. However, Mary has hidden herself by anchoring herself and hiding by hugging the wall underneath the balcony. Conan takes a picture of a car parked on the ground floor below the balconies and decides to take a snapshot of the underside of the balcony, just to be certain. Masumi rushes to interrupt him on some pretense. Conan then drops his voice-changer on his way back inside. Mary picks it up, and later uses it in place of Conan to solve the case. When the culprit tries to flee by leaping over the balcony of the murder room over to their room, Mary takes him down single handedly using skills comparable to that of the secret service. Masumi rushes after Conan who has followed the suspect, calling out "Mama". Once Conan has left, Mary and Masumi discuss what information the Soul Detective had, which was that before Kohji's death, Asaka was seen holding a hand mirror and thinks that it means that Asaka is a woman. Mary warns Masumi about Conan saying that "it is like encountering a demon in the darkness" (暗がりに鬼を繋ぐが如く), and that he is not the same boy they met 10 years ago. Conan goes home and looks at the snapshot he has taken of the underside of the balcony. He theorizes that Mary could have been Asaka. Later Gin uses the same demon line that Mary used to refer to Kogoro.

A Chance Meeting at the Beach (Manga: 972-974, Anime: 881-882)

A flashback to 10 years ago at the beach.

10 years ago at a beach somewhere in Japan, Shuichi reunited with his family after his 7 years in the US. Mary had an off-screen fight with him where they both managed to injure each other's eye. Through out the case Mary warns him to stop investigating the disappearance of his father. She also tells both Shuichi and Masumi not to do things that got them involved in the case, because there are people out there that are after them.

Crimson School Trip Case (Manga: 1005, Anime: 928)

After the case is solved, Masumi calls Mary and informs her about the drug that will return her back to normal, after witnessing Shinichi's appearance. Mary ordered Masumi to find the developer of the drug and obtain it. Once she succeeds, Mary declared that they will stop running from hotel to hotel and counterattack.

Antique Facet Case (Manga: 1038, Anime: 1020)

At the end of the case, Sera asks her mother about her "50:50" catchphrase, Mary revealed that it is a line that her husband used to say and her son Shuichi inherited from him. Mary asks Sera if she can gets her hands on the drug, which the latter told her that it is difficult for the moment since Subaru Okiya is standing in her way. Mary asks her if he is such a noteworthy person, however, Sera is more concerned about whether Subaru is her brother Akai or not, since he's using the same "50:50" catchphrase as her brother.

Sisters' Birthday Party Murder Case (Manga: 1047-1050, Anime: TBA)

Mary receives a call from Masumi, informing her that Conan brought the antidote that can returns her to her orginal body, and it is blue and white compared to the drug she was forced to take, which is red and white. Mary ordered her daughter to steal the antidote if possible. Later, Mary calls her daughter, asking if she was able to get the antidote, which Masumi responded that she was involved in a poisoning murder case. Hearing about poison, Mary started to remember her shrinking moment. Several months ago, Mary was supposed to meet her husband at Vauxhall Bridge in London, Tsutomu Akai appeared in front of her, however Mary realised that he isn't her husband after giving him false informations about her daughter. Tsutomu is revealed to be Vermouth in disguise, who intended to poison her with APTX 4869. Vermouth feeds Mary the drug with her mouth directly, which is created by her sister. Mary then jumps into the river due to the effect of the drug being very instant. After Mary shrinked, she returned to Sera, explaining to her the whole situation. Later, Mary and Sera witnessed Conan proclaiming himself as Holmes' apprentice during Minerva's match on TV, and remembered the same proclamation of Shinichi 10 years ago. The two realised that Conan is Shinichi who shrunk the same way as Mary, however, he has a way of returning as Shinichi to board a plane to London. Since then, Mary ordered Masumi to get closer to him, in order get their hands on the antidote.

Non-canon plot overview

Dimensional Sniper (Movie: 18)

Mary is only shown twice at dawn under her hotel bed's blankets.

The Scarlet Bullet (Movie: 24)

Mary is shown working with her daughter Masumi to find a VIP from England who was kidnapped. She is seen attacking Subaru (Shuichi Akai) landing a few clean blows before running disappearing. She is also seen towards the end of the movie as she hides in Subaru’s car and waits for him to jump in. She points the gun to his head and threatens him and the FBI as they risked the life of an important VIP.

Relationship

Tsutomu Akai

Tsutomu is her husband, who she lost around 17 years prior to the series. In his last message, he advice them to hide in Japan and think of him as dead due to that he has made himself some enemies. Although much of their relationship remains unknown, she knew her husband enough to easily see through Vermouth's disguise and in contrast to her distant and hardened exterior, the fact that Tsutomu was possibly dead was enough to cause her to cry, showing she cared deeply for him.

Shuichi Akai

Shuichi is her oldest son. She didn't approve at first of his decision to join the FBI and investigate his father's death, but eventually she gave him her blessing.

Shukichi Haneda

Shukichi is her second-oldest child and youngest son. It's not certain how she feels of him, but she keeps track of his Shogi-career and seemed happy when he became the seven-crowned king.

Masumi Sera

Masumi is her only daughter and youngest child, who was born after the family moved to Japan. Currently the two of them switch between hotels to hide themselves. Mary cares for Masumi, but doesn't trust her entirely (probably due to her extreme youth).

Kohji Haneda

Mary reacted to Kohji's name when she heard Kogoro mention it. It's possible that the Akai family, including Mary, might know Kohji in person.

Plot Exposition

Hints that Mary is the Akai family mother

These were the hints that fans used to determine that Mary was the Akai family mother prior to the end of the Soul Detective Murder Case where Masumi called Mary "mother", and the flashback to Shinichi and Ran meeting the Akai family on a beach.

• Mary shares a resemblance to Shuichi Akai and Masumi Sera, and it was known from Masumi's earlier testimony that Akai family's mother also passed her looks into Shuichi and Sera.
• Mary is unusually mature while talking to Masumi. She gave Masumi instructions despite Masumi being apparently older and a skillful detective in her own right.
• Mary was happy when Shukichi (who was later revealed to be the middle brother of the Akai Family) won his 7th Shogi title.
• Mary seems to have some knowledge abut wiretaps, she also demonstrated the ability to a balcony by a thin rope/wire and hug the wall like a ninja. She was also able to take down a fully grown man by herself. Conan described the damage as "a copped blow to a vital spot, similar to the techniques used by the secret service." A normal middle school girl wouldn't be able to do this.

Mary is an adult shrunken by APTX 4869

Mary acts like an adult despite having the appearance of a middle-school aged female. When Masumi and Mary speak, the speech honorifics are not those appropriate for an elder Masumi talking to a younger girl. Instead, they appear to indicate the two are on equal levels, or even reverse with Mary expressing greater seniority. In addition, Mary's voice actor in the anime, Atsuko Tanaka, has a deep and sultry voice which is often used to portray mature female characters.

The secrecy surrounding Mary, as well as Masumi's attempts to get her to trust Conan, whom Masumi knows is a shrunken Shinichi, might be indications that Masumi is trying to get the child help about an APTX 4869 problem. This plot point is finally canonized in manga chapter 1049, when a flashback reveals a fateful confrontation between Mary and Vermouth which resulted in Mary getting force-fed the APTX.

Mary is the sister of Elena Miyano

This very popular fan theory was born after Gosho hinted that two mother characters are sisters. After it was confirmed the sisters were not the previous most popular choice Yukiko Kudo and Chikage Kuroba, and that the Akai family mother was one member of the sister pair, fan suspicion fell squarely on Elena Miyano as the other mother. After all, both women are British. Gosho has given evasive answers when asked about Elena and the Akai family mother being related, which is his habit when a fan theory is correct but he can't admit to it. In file 1049, it is confirmed that Elena and Mary are sisters, when Vermouth said "How does it feel to detach from this world with the drug that your sister made?" after poisoned Mary with APTX 4869.

Mary is a British SIS/MI6 Agent

Mary is British and has several unusual skill sets that match those of other spy-like characters in Detective Conan. Mary has knowledge of incapacitating martial arts that can bring down adult men despite her size, extraordinary flexibility and climbing skills that allowed her to hide below a balcony like a ninja, and knowledge of listening devices and hidden microphones.

Because of her British nationality, the theory that she is a member of the British Secret Intelligence Service, often known as MI6, has gained traction in many Detective Conan fandoms. In chapter 1049, that detail is inserted into Detective Conan canon when in a flashback Vermouth expresses regret that she cannot disguise herself as Mary to infiltrate MI6 for the time being when she is forced to assassinate the latter.

Speculation

At the time Mary was introduced, her relationship to Masumi Sera was unknown. Masumi testifies that she has two older brothers: Shuichi Akai and an unknown brother (later revealed to be Shukichi Haneda) living in Japan. She says her father is dead, and her mother lives overseas in America. Masumi says she doesn't have any more relatives close enough to depend on. Masumi only started claiming to have a "younger sister from outside the domain" after the unknown child coached her to use that cover story if Conan asked about her. She is currently being financially supported by a friend of her father's. If Masumi has told the truth, minus what she said about having a "younger sister from outside the domain", that leaves relatively few options for Mary's identity assuming the child is related by blood somehow to Masumi. In file 972, Mary is revealed to be the Akai family's mother.

Gallery

• 

  Mary's original appearance in the anime adaptation of the case (episode 756).

• 

  Mary as she originally appeared in file 875.

• 

  Mary in file 899.

• 

  Mary 17 years ago

• 

  Mary 10 years ago

Trivia

• In File 1038 its reveal that like Shuichi and Tsumotu, she uses the phrase “It was 50:50 so we’re both to blame”.
• It is revealed in many manga panels that Mary is left-handed, just like her son.
• Mary usually coughs, properly due to the side effects of APTX-4869.
• Mary's seiyuu is Atsuko Tanaka.

See also

• Characters
• Akai family