Ayako Mochizuki is a 35-year-old detective. She is a hard worker and seeks out justice, but she lacks flexibility. Ayako Mochizuki investigates a murder case. From the evidence she collects, she targets Haruto Hidaka as the murder suspect. Haruto Hidaka is a chemistry researcher and he runs his own company. He is smart and proficient with his work, but he is also a psychopathic murderer. Right before Ayako Mochizuki arrests him, their bodies are switched.