They vow to each other not to be shot in their final case – a cliché Franz Leitmayr and Ivo Batic are determined to avoid after 35 years of service. But their farewell case turns out to be extremely dangerous: deep beneath the city, an unidentified woman's body is discovered. From just a few clues, the investigators piece together a perpetrator profile – everything points to a phantom who roams Munich apartments, targeting young women. Together with Kalli Hammermann, they build up the evidence against a suspect, but he always seems to be one step ahead. When they themselves become the targets, the finale raises the question of whether they can keep their promise.