For Hitchcock and Patricia Highsmith both, the doppelgänger, the double, is a shark in the murky waters of innocence and culpability. In this Faustian treatment of the transference of guilt, Robert Walker plays the psychopathic sprite Bruno, who empathically makes himself the agent for Farley Granger’s unannounced desire to murder his wife. The screenplay, coauthored by Raymond Chandler from Highsmith’s 1950 novel, serves up Walker’s style of smirking innuendo on a silver tray. In no other Hitchcock film is sexuality so obsessively suffused with black humor; we know that Hitchcock is Bruno’s double.