Arguably Zinnemann's most underrated film, this harrowing noir is a vivid evocation of survivor's guilt directed by a man who had lost much of his family in the death camps. Unlike most noirs, which open with its protagonists in desperate straits, the film derives much of its power from the contractor's gradual descent from a seemingly normal life into a perverse nightmare realm. While the highly improbable plot is a bit baroque for straight drama, and the character of Joe is less a human being than a projection of Frank's guilty conscience, the elements still mesh beautifully in the service of the film's tough-talking expressionism. In one unforgettably corrosive and spectacularly photographed sequence, Frank careens wildly through downtown L.A., ending up in a dive where he finds himself taking advice from a well-worn hooker (Mary Astor) and her hitman friend (Berry Kroeger). Heflin mixes fear, confusion, and desperation in a typically multi-layered performance, and Ryan is disturbing as the obsessive, embittered cripple, but it's Astor's rock-hard yet bizarrely compassionate prostitute than lingers in the mind. Even better is the rich chiaroscuro of Robert Surtees' camera work, in which shadows slice bodies and cover faces until, like the contractor, we no longer have the vaguest idea where we are.