He Walked by Night (1948)
A methodical lone burglar with an ex-cop's grasp of police procedure evades an LAPD manhunt across Los Angeles, until forensic detective work traps him in a chase through the city's storm drains.
Jack Webb plays only a minor police chemist here, but the film’s procedural rigor — and its real LAPD technical advisor — sent him off to create Dragnet; John Alton’s shadow-heavy photography of the storm drains remains its most enduring image.
Background
He Walked by Night follows a methodical lone burglar with an ex-police officer’s understanding of investigative procedure as he evades a citywide manhunt across Los Angeles, eventually being trapped through careful forensic detective work in a tense chase through the city’s storm drains. Jack Webb appears in a small role as a police chemist, and his experience working with the film’s real LAPD technical advisor is widely credited with inspiring him to create the long-running radio and television series Dragnet shortly afterward.
What to watch for
Watch for cinematographer John Alton’s shadow-heavy visual style, particularly in the climactic chase through the storm drains, which remains the film’s most enduring and frequently referenced sequence. The film’s emphasis on procedural accuracy and its semi-documentary tone, narrated passages describing real police methods, set it apart from more purely melodramatic noir films of the period and helped establish a template for the police procedural genre that followed in film and television.
