Tantei no Tantei

Sasaki Rena is training hard in the gym of Suma Yasuomi's Detective Agency “Suma Research.” Rena is the sole detective in the agency's “Anti-Detective Department” that investigates detectives, but she is soon joined by Minemori Kotoha, a newbie brought in by Suma. Suma tells Rena that Kotoha is to be her assistant, but Rena insists she can handle the department herself.

While Sasaki Rena is out, Abiru Yoshinori arrives at the Suma Research Company. When Suma Yasuomi and Minemori Kotoha go to meet him, he informs them that he met Rena the previous day. Furthermore, he gives them a small box tied with a ribbon and asks them to give it to Rena. Suspecting a listening device may be planted inside the box, Kotoha decides to check at the suggestion of the Detective Department's Doi Shuzo.

Yabuki Yoko, the doctor who performed the DNA analysis of Sasaki Sakura five years ago, tells Sasaki Rena that suspect Okao Shinya, who was thought to have died with Sakura, is still alive. Furthermore, he may be involved in the kidnapping of a young girl that occurred a few days prior, and the police are currently working with a detective to capture him. Rena asks about the detective, but Yabuki says she doesn't know anything about him.

Following Abiru's instructions, they head towards the suspect's location. Suddenly, the sound of footsteps cuts through the tense air. As the detectives gaze into the dimly lit room, they find Sasaki Rena covered in wounds and dragging a metal pipe. When Rena comes to Abiru, she shifts her gaze to Yabuki Yoko standing at his side.