 Lionel AtwillIvan Igor | Ivan Igor |
 Glenda FarrellFlorence Dempsey | Florence Dempsey |
 Allen VincentRalph Burton | Ralph Burton |
 Fay WrayCharlotte Duncan | Charlotte Duncan |
 Frank McHughJim | Jim |
 Edwin MaxwellWorth | Worth |
 Arthur Edmund CareweProfessor Darcy | Professor Darcy |
 Gavin GordonGeorge Winton | George Winton |
 Matthew BetzHugo | Hugo |
| BBull AndersonOtto | Otto |
 Holmes HerbertDr. Rasmussen | Dr. Rasmussen |
 Claude KingMr. Galatalin | Mr. Galatalin |
 William B. DavidsonDetective (Uncredited) | Detective (Uncredited) |
 Guy UsherDetective (Uncredited) | Detective (Uncredited) |
 DeWitt JenningsPolice Captain, 12th Precinct | Police Captain, 12th Precinct |
 Robert HomansDesk Sergeant, 12th Precinct | Desk Sergeant, 12th Precinct |
 James DonlanMorgue Attendant (Uncredited) | Morgue Attendant (Uncredited) |
 Thomas E. JacksonDetective at Morgue | Detective at Morgue |
 Frank DarienAutopsy Surgeon (Uncredited) | Autopsy Surgeon (Uncredited) |
 Wallis ClarkAutopsy Surgeon's Assistant (Uncredited) | Autopsy Surgeon's Assistant (Uncredited) |
 Monica BannisterJoan Gale | Joan Gale |
 Robert Emmett O'ConnorPolice Sergeant by Christmas Tre | Police Sergeant by Christmas Tre |
 Lon PoffTall Thin Henchman (Uncredited) | Tall Thin Henchman (Uncredited) |
 Max BarwynMuseum Visitor (Uncredited) | Museum Visitor (Uncredited) |
 Wade BotelerAmbrose (Uncredited) | Ambrose (Uncredited) |
 Otto HoffmanIgor's Assistant (Uncredited) | Igor's Assistant (Uncredited) |
| PPerry IvinsCopy Editor (Uncredited) | Copy Editor (Uncredited) |
 Margaret MannWax Figure of Queen Victoria (Uncredited) | Wax Figure of Queen Victoria (Uncredited) |
 Pat O'MalleyPlainclothesman (Uncredited) | Plainclothesman (Uncredited) |
 Milton KibbeeReporter (Uncredited) | Reporter (Uncredited) |
