"A film projectionist longs to be a detective, and puts his meagre skills to work when he is framed by a rival for stealing his girlfriend's father's pocketwatch."
Buster Keaton
as Projectionist / Sherlock, Jr.
Kathryn McGuire
as Girl
Joe Keaton
as Girl's Father / Man on Film Screen
Erwin Connelly
as Hired Man / Butler
Ward Crane
as Sheik / Villain
Doris Deane
as Girl Who Loses Dollar Outside Cinema (uncredited)
Christine Francis
as Candy Store Girl (uncredited)
George Davis
as Conspirator (uncredited)
Kewpie Morgan
Steve Murphy
John Patrick
Betsy Ann Hisle
as Little Girl (uncredited)
Ford West
as Theatre Manager / Gillette (uncredited)
Byron Houck
Director of Photography
Elgin Lessley
Fred Gabourie
Art Direction
Director
Editor
Joseph M. Schenck
Producer
Clyde Bruckman
Screenplay
Clare West
Costume Design
Technical Supervisor
Joseph A. Mitchell
Story
Walter C. Reed
Assistant Director
Jean C. Havez
Ernie Orsatti
Stunts