Episode 652: The Design of Poison and Illusion (Eye)
Scenario: Heiji explains Kazuha went to Wakamatsu's home in Osaka per the letter's instructions where she finds a disguised person with the word "EYE" carved into the bathroom tiles. The person causes a blackout, sneaks away, and the carved words disappear. Heiji elaborates that Wakamatsu was murdered in his bathroom in Karuizawa, Nagano and that the culprit was hinting a dying message had been left on the tiles. Heiji and Kazuha has Kogoro, Ran, and Conan join them to interview Wakamatsu's widow and close companions who were in his home on the day of his death. During the interview, Ikuro Wakamatsu, the victim's son, dies after eating a poisoned baumkuchen.
Heiji reads a letter he received from an already dead man and old acquaintance of his mother, design company president Kohei Wakamatsu, who was killed a month earlier in his Karuizawa villa.
Heiji proves the letter was sent by someone else by showing the postmark was mailed ten days after the murder, which occured during the wife's birthday party in the restroom. Heiji reads the letter from the culprit wanting Heiji to solve the crime, and is given the house key to the villa in the letter. Kazuha went with three of her friends to look at the home in Osaka while Heiji had a cold. They find a strange looking man in the bathroom who vanished when the lights went out for a moment. Kazuha remembers seeing the word "EYE" scratched in the wall written in english. Heiji went to take a closer look after feeling better, but the house was being rebuilt. He points out that Kohei Wakamatsu's dying message was erased when police arrived as evident by the blood on the victim's finger but no smear. Ran notes that the deceased could have had glue, which was true since he was re-tiling his bathroom at the time, identical tiles to the house in Osaka. The culprit could have flipped the tiles to hide the message. The tiles had a coloring effect where they would get lighter from top to bottom. Everybody, except Sera who wasn't invited, upon reaching the home of the dead man's widow, Serika Wakamatsu, and the son of the dead president, Ikuro Wakamatsu, bursts in demanding dinner. Two more men arrive: Masashige Shiina, the senior managing director, and Sumio Fujinami, the chief designer. Masashige brought baumkuchen, a kind of cake, and Fujinami blurts how he tasted a piece to assure everyone it isn't poisoned. Serika calls for the secretary, Yoshimi Satake, to make some tea while everyone waits. In the living room, the housekeeper Sakurako Yonehara says she saw the dying message before it was erased. His blood was used to write the letter "S". During the cake cutting, Ikuro cuts to the chase wanting to discuss the new company president. As he is explaining why he should be president, he picks up a piece of baumkuchen and drops dead from poison in front of everyone.
The police arrive and investigate how the cake piece that Ikuro ate was the only poisoned piece. Conan points out a capsule in a tea cup which could have been what carried the poison. As the pill is biodegradable, the empty capsule was put in the tea after the poisoning so destroy the evidence. The baumkuchen was cut evenly into eight pieces, the only poisoned piece was that consumed by the victim, and Heiji takes notice of the "S" in the dying message. As it so happens, all five living suspects have an S in their name: Serika, Sumio, Shiina, Satake, and Sakurako.
