The Detective Boys discover officer Chiba's has been vandalized with a threatening word. Realizing is the culprit is the same person who has been on a vandalism spree that month, the Detective Boys push Chiba into investigating it with his first love, Naeko Miike. They investigate an underground parking lot where the vandalism occur; There, a rear-end collision is caused by the vandalism culprit. The police seal off the parking lot leaving three people as the suspects. During the investigation, a draft removes Naeko's hat revealing her face to Chiba.