On a drizzly after‑hour, the Detective Boys spot a homicide across the rain‑slicked boulevard under the dim glow of traffic lights. Encumbered by heavy traffic, the assailant flees and Conan Edogawa receives a solitary hint from a dying officer. Several days later, another inspector is discovered dead in a parking area, unsettling the entire force. Suspecting an insider, every cop lacking an alibi becomes a suspect. Even while on guard, they are outsmarted and endure yet another strike—this time with Ran Mouri caught in the crossfire.
Shaken, Ran awakens in the infirmary with retrograde amnesia, recalling nothing of her past. Shortly discharged, she battles to recover memories and fears the killer will target her for what she saw. While protected by friends and relatives, it falls to Conan to assemble the evidence and unmask the murderer before another attack occurs. And the tension builds with each passing hour. As the city sleeps, the danger looms in silence.