He Walked by Night is a 1948 American film directed by Alfred L. Werker and Anthony Mann and starring Richard Basehart, Scott Brady, Roy Roberts, Jack Webb, and Whit Bissell. Sergeant Marty Brennan (Brady) and Sergeant Chuck Jones (Cardwell) are Los Angeles police officers assigned to the case to catch Roy Morgan (Basehart), a killer who recently killed a policeman. When Paul Reeves (Bissell) buys stolen electronics equipment from Morgan, he informs the police of the killer's identity and his whereabouts. Morgan, however, has made a radio that allows him to listen to police frequencies. After a close call where he is shot, he changes his game plan. Morgan then begins a series of robberies, but when a shell casing is matched to the other crimes, Captain Breen (Roberts) is able to gather enough evidence to find the killer. A climactic shootout in the sewers of Los Angeles is one of the film's highlights.