C.I.S. - Chaoten im Sondereinsatz (2010)

Years ago, forensic pathologist Lukas Maler ruined his career by accidentally rendering evidence against the 24-Hour Killer, a serial murderer, unusable. The killer had given his victim an alarm clock with a 24-hour countdown, then killed the victim when the time ran out. Maler now works as a butcher. When the 24-Hour Killer strikes again using the same method, Maler is brought back onto the investigative team. The team is led by his ex-wife, Diana, and at first the two of them can barely get along; after they sleep together, their relationship eases. Lukas discovers that the accident in which the evidence was destroyed was deliberately caused. So the 24-Hour Killer must have an informant on the team. Fabricated evidence turns up that strongly implicates Maler. As a result, he is sent to prison, but manages to escape with the help of a fellow inmate’s escape plan. Maler and his colleague Gonzalez discover that the 24-Hour Killer is operating out of a crematorium. In the showdown, Diana and Gonzalez are nearly burned alive in the crematorium while Maler fights the killer, who turns out to be his superior, and eventually overpowers him.