Robert Walker wears an unidentified watch

Strangers on a Train (1951) is Alfred Hitchcock's adaptation of Patricia Highsmith's first novel, and Robert Walker plays its engine, Bruno Antony, the charming stranger who corners tennis player Guy Haines on a train and proposes a criss-cross: Bruno will kill Guy's wife, Guy will kill Bruno's father, and neither will have a motive the police can trace. Guy treats it as idle talk. Bruno does not. He follows Guy's wife Miriam to an amusement park and strangles her, then spends the film expecting Guy to make good on a deal Guy never accepted. Walker had built his career on gentle, romantic leads, played hard against type here, and died that August at thirty-two, two months after the film opened.

In this scene Bruno is at the railroad station in Metcalf, the town where Miriam lives, checking his wristwatch as he times his plan. A crossbuck behind him reads STOP LOOK AND LISTEN. The watch sits on his wrist on a dark strap, but the camera keeps its distance and no maker is legible, so the watch stays unidentified.