Charlie's visit to Paris, ostensibly a vacation, is really a mission to investigate a bond-forgery racket. But his agent, apache dancer Nardi is killed before she can tell him much. The case, complicated by a false murder accusation for banker's daughter Yvette, climaxes with a strange journey through the Paris sewers.
| Actor | Role |
|---|---|
 Warner OlandCharlie Chan | Charlie Chan |
 Mary BrianYvette Lamartine | Yvette Lamartine |
 Thomas BeckVictor Descartes | Victor Descartes |
 Erik RhodesMax Corday | Max Corday |
 John MiljanAlbert Dufresne | Albert Dufresne |
 Murray KinnellHenri Latouche | Henri Latouche |
 Minor WatsonInsp. Renard | Insp. Renard |
 John QualenConcierge, Dufresne's Hotel (bit) | Concierge, Dufresne's Hotel (bit) |
 Keye LukeLee Chan | Lee Chan |
 Henry KolkerPaul Lamartine | Paul Lamartine |
 Dorothy ApplebyNardi | Nardi |
| PPerry IvinsBedell, Lamartine's secretary | Bedell, Lamartine's secretary |
 Ruth PetersonRenee Jacquard | Renee Jacquard |
| EEddie VitchSketch Artist (uncredited) | Sketch Artist (uncredited) |
 Lynn BariClub Patron (uncredited) | Club Patron (uncredited) |
 Harry CordingGendarme Arresting Yvette (uncredited) | Gendarme Arresting Yvette (uncredited) |
 Gino CorradoPierre (uncredited) | Pierre (uncredited) |