Cast
Gail MacKenzie
Lt. Robert «Clem» Clemens
Sheriff Josh Peters
Seaman Fred Johnson
Sally
Sonarman 2nd Class Morty Beatty, not listed in creditsMonster Victim, not listed in credits 
Deputy Larry, not listed in creditsClark, not listed in credits 
Rear Admiral Greenhouse, not listed in creditsDeputy Scotty, not listed in credits Deputy Brewer, not listed in credits The Other Lock Watchman, not listed in credits 
Boy with Morty's Cap, not listed in creditsHelicopter Crewman, not listed in credits Coroner Nate Brown, not listed in credits George Blake - Lab Assistant, not listed in credits 
Patterson, not listed in credits
Watchman at Lock 57, not listed in credits
Lewis Clark Dobbs, not listed in credits
Mrs. Simms, not listed in creditsа
Seaman Howard Sanders, not listed in credits
Davis - Resort Owner, not listed in credits
Radioman Wyatt, not listed in credits
Deputy, not listed in creditsCapt. Masters, not listed in credits 
