Directed by
| John Francis Dillon | ||
Writing Credits
| Jo Swerling | ... | (story "In the Secret Service") |
| Jo Swerling | ... | (dialogue) |
Cast (in credits order)
| Jack Holt | ... | Jack Hart aka Quinn | |
| Constance Cummings | ... | Julie Arnold | |
| Boris Karloff | ... | Jim Henderson | |
| Claude King | ... | Arnold | |
| Bertha Mann | ... | Nurse Edwards | |
| Edward Van Sloan | ... | Dr. August Steiner / Dr. Alec Munsell / Mr. X | |
| Willard Robertson | ... | Capt. E.J. Hawkes | |
| Thomas E. Jackson | ... | Agent Burke (as Tommy Jackson) | |
| Rest of cast listed alphabetically: | |||
| Jessie Arnold | ... | Eastland Hospital Nurse (uncredited) | |
| Clarence Burton | ... | Agent Gorman (uncredited) | |
 |
Rodney Hildebrand | ... | Cell Block Guard (uncredited) |
| Martha Mattox | ... | Hotel Ansonia Maid (uncredited) | |
| Louis Natheaux | ... | Arnold's Secretary / Graveyard Keeper (uncredited) | |
| Harry Tenbrook | ... | Man in Black / Henchman in Boat (uncredited) | |
Produced by
| Harry Cohn | ... | producer (uncredited) |
Cinematography by
| Ted Tetzlaff | ... | (as Teddy Tetzlaff) |
Editing by
| Otis Garrett | ||
Second Unit Director or Assistant Director
| Edward Sloman | ... | assistant director (uncredited) |
Sound Department
| Glenn Rominger | ... | sound engineer (uncredited) |
Script and Continuity Department
| Dorothy Howell | ... | continuity |
