Ellery Queen solves a mystery involving a valuable stamp.
You can now watch The Mandarin Mystery online on the following streaming providers in the United States.
| Directing | Ralph Staub | Director |
| Writing | Frederic Dannay | Original Story |
| Writing | Manfred Lee | Original Story |
| Writing | Cortland Fitzsimmons | Screenplay |
| Writing | John Francis Larkin | Screenplay |
| Writing | Gertrude Orr | Screenplay |
| Writing | Rex Taylor | Screenplay |
| Production | Nat Levine | Producer |
| Production | Victor Zobel | Producer |
| Camera | Jack A. Marta | Director of Photography |
| Editing | Grace Goddard | Editor |
| Costume & Make-Up | Eloise | Costume Design |
| Directing | Philip Ford | Director |
| Editing | Murray Seldeen | Supervising Film Editor |
| Sound | Harry Grey | Music |
| Sound | Hugo Riesenfeld | Original Music Composer |
| Sound | Milan Roder | Original Music Composer |
| Sound | Heinz Roemheld | Original Music Composer |
| Sound | Harry Jones | Sound Engineer |
