Conan is sick with a cold and receives a video call from the Detective Boys. During the call, the Detective Boys receive a plea from Masao Urafune to save him from the people posing as his parents. Disregarding Conan's advice to call the police, the Detective Boys decide to ask the neighbors about the Urafune family. They learn Masao is a compulsive liar and decide to ask him directly in his apartment on the premise of playing karuta. Meanwhile, the criminals threaten to kill Masao's mother if he attempts to reveal his situation to Detective Boys. As the game progresses, Masao plays in an aggressive manner but makes no effort to win, leading Haibara to realize he intends to use his cards to send a message.