S01E329: Friendship Can't Be Bought with Money (1)

Ayumi decides that on the Detective Boys camping trip, she will attempt to address Ai Haibara by her first name and to call her "Ai-chan". During the camping trip, they run into four college students who offer them a ride in their campervan to the top mountain to watch fireworks. While driving down the mountain, one of the four college students, Yasumi Shirafuji, is found on the road dead.