Conan knocks Sonoko down with his Stun-Gun Wristwatch accidentally which he was targeting for Kogoro when Ran suddenly hugged him from behind. Conan then goes ahead with solving the case as Sonoko instead of Kogoro. Conan as Sonoko's voice then says that the turtle wasn't stolen but has been vanished out of sight.
Conan asked for Kogoro lighter and ask him to drop into the tank, from right above, behind the plate. Kogoro noticed that it didn't fell which he later see that the lighter is stuck at the plate. According to Sera, it is really strong magnet that the lighter got stuck at the plate. Kogoro and Ginzo doesn't believe both that the turtle got disappeared from only magnet. Nakamori said that the turtle got a gold necklace which isn't attracted to gold which that thing that would stick is the necklace clasp.
According to Conan: If the diamonds that was around the belly of the turtle synthetic diamonds, it would maybe stick to the magnet. If someone created synthetic diamonds, sometimes that iron in the solvent into the crystal as a inclusion.
The turtle was swimming in the tank which that it was impossible to hold the crystal in place simply by magnetism, but the plate had enough strength and something was used to attract the turtle with it.
Kogoro sees that his lighter is stuck against the plate which he also have noticed that it has been covered in glue. Nakamori wonders how Kid got the turtle up unto the plate.
Conan said that Kid used bait, It is known that Kid uses little iron dust around the turtle's food and it was spread around the tank so that it was on the plague which that the turtle's high acute sense of smell has been risen up from the bottom of the tank to float beside the glass.
The device that was used to spread the bait came from the chandelier. It was set on motion when the target covered up the tank. The length of the turtle is around 10cm and a plate with a large size could easily hide the turtle behind it.
Nakamori later figured out the the turtle must still stay behind the plate, which he also thinks that something like that is impossible. Conan as Sonoko's voice then explains that there is someone who didn't have a body inspection, which Ran thinks that it she was the one, but Conan said that the turtle would easily. Conan as Sonoko's voice then says that Jirokichi has the turtle. Nakamori inspects the inside of Jirokichi's jacket which turn out to be true. Jirokichi then tells Nakamori that he has a explanation why he hidden the turtle. Conan as Sonoko's voice then tells that it is the card that Kid send him after the heist with the true text:
"I can't imagine that a turtle covered in synthetic diamonds that got stuck to a magnet is carrying the Blush Mermaid and the name of the turtle is Poseidon, like the sea god from Greek myths. But the owner who was a Italian actress should have named the turtle Neptune after the sea god of the roman myths. If you don't want it known that you spent a small fortune buying a dubious jeweled turtle, then it would be wise if you remove it discretely."
So Kid knew the Blush Mermaid was a fake, and used magnets for his trick.
It is all true what Conan said through Sonoko. Nakamori figured out the reason why Jirokichi was constantly telling them to wrap things up. Kogoro then ask Sonoko what has happened to Kaito Kid. Conan as Sonoko's voice then says that Kid has been escaped alongside with the crowd pushing around the entrance.
While going back Conan privately exposes Kaitou Kid who is under the disguise of Masumi Sera. When Kid asks how did he know, Conan tells him that it was because of the magnet and that he was holding the magnet with him and the trick wouldn't work unless he split everyone into groups to do a body search. Conan also notes the fact that Kid was surprised when Ran and Sonoko wanted to group with him was because from above he thought Sera was a boy. When Kid surprisingly asks that Sera was a girl. Conan says yes but let Kid go because of the help he gave them during the mystery train case by disguising as Shiho Miyano. Conan comments that only he will forgive him and referring to Sera, who running in her underpants kicks Kid in the face but before she can catch him he escapes with his hang glider. Sera then tells them that she had gone to the men's restroom where Kid knocked her out with a stun-gun because the ladies room was filled and that she wanted to get it done. Conan secretly comments that he understands why Kid made a mistake. Sera then asks Ran whether she say any strange man when she picked up her hat to which Ran asks her why is the hat so special to her. She says that her "late brother" (referring to Shuichi Akai) used to wear hats like these and she is wearing them to copy Akai. So Sera mentions that her hat resembles her late eldest brother's hat and it has the same feel as if he wore it ever since they left the Bell Tree Express Train. She also comments on how the hat Ran found had the same wear of shape that he had in his hats but that there is no way it could be possible.