A convict who has just escaped from Alcatraz Prison takes over a passenger ship. Two of the ship's crew hatch a plot to overpower him and rescue the ship's passengers.
| Actor | Role |
|---|---|
 Gail PatrickDale Borden | Dale Borden |
 Lloyd NolanRaymond Grayson | Raymond Grayson |
 Harry CareyCaptain Glennan | Captain Glennan |
 J. Carrol NaishSteve Murkil | Steve Murkil |
 Robert PrestonRobert MacArthur | Robert MacArthur |
 Anthony QuinnLou Gedney | Lou Gedney |
 Dennis MorganFirst Mate Rogers (as Richard Stanley) | First Mate Rogers (as Richard Stanley) |
 Richard DenningHarry Vay | Harry Vay |
 Konstantin ShayneMurok | Murok |
 Eddie MarrDave Carter | Dave Carter |
 Emory ParnellOlaf | Olaf |
 Paul Fix'Nails' Miller | 'Nails' Miller |
 Virginia ValeDixie (as Dorothy Howe) | Dixie (as Dorothy Howe) |
 Monte BlueOfficer | Officer |
 John Hart1st Radio Operator | 1st Radio Operator |
| PPhil WarrenRadio Operator (as Philip Warren) | Radio Operator (as Philip Warren) |
 Porter HallMatthew Talbot | Matthew Talbot |
 Tom TylerGus Banshek | Gus Banshek |
 Virginia DabneyBonnie Larkin (uncredited) | Bonnie Larkin (uncredited) |