Chinese detective Charlie Chan (Sidney Toler) is on his way to San Francisco to take over a murder case when he meets a woman, Mrs. Conover (Mary Gordon), who is searching for her missing daughter and a young man, Jeff Tilford (Bruce Kellogg), who is looking for his missing fiancee. Investigation by Charlie discloses they are both looking for the same girl, Mary Conover (Tanis Chandler). Chan eventually uncovers a murder gang, which has been collecting the life insurance of its victims.