A burnt-out Berlin cop investigating his 652nd case slowly loses the ability to discern the differences between the grim realities of the job and a decaying personal life as his mental instability grows progressively worse. His latest case is particularly nasty and puzzling, but Detective Bernie Kominka (Gotz George) finds himself strangely pleased, for it distracts him from his tumultuous home life wherein his wife grows fussy and distant, and his nearly lunatic son proclaims his undying hatred for him. The mystery involves the apparently sexually-motivated mutilation, beating death, and robbery of a young man. During his initial investigation of the crime scene, Kominka notes a yellow umbrella that is surreptitiously picked up by a young woman. While vainly searching for clues, Kominka's marriage finally crumbles, but not before he is suspended by his boss/brother-in-law Hecht (Christian Redl) during a heated argument. With no work and no family, Kominka, who seems to be teetering on the brink of a breakdown without realizing it himself, starts looking for the woman and the missing umbrella. During his search, he learns that the victim's ex-wife has become a suspect and that the deceased had been selling his son to pedophiles. Kominka finds the woman, Anna Weller (Corinna Harfouch) soon enough. A recent divorcée, she is as vulnerable and fragile as he is. Without identifying himself as a cop, Kominka picks Anna up at a singles bar and the two embark upon a decidedly sexual and unhealthy relationship that only worsens the situation.