Bill Rogers as John Stone

Elizabeth Wilkinson as Helene Stone

William Kerwin as Dr. Hank Tyson (as Thomas Wood)

Lawrence Tobin as Detective Crane

Ted Schell as Lord Gold

Otto Schelssinger as Dr. Howard Helsing

Eleanor Vaill as Hester Avery

Herschell Gordon Lewis as The Limey Seaman / Baron Khron (voice) (as Seymour Sheldon)

Dolores Carlos as Sherri Morris