The Design of Poison and Illusion (Eye) 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.