Glen or Glenda

Bela Lugosi

Scientist

Lyle Talbot

Inspector Warren

Timothy Farrell

Dr. Alton / Narrator

Dolores Fuller

Barbara

'Tommy' Haynes

Alan / Anne

Charlie Crafts

Johnny (as Charles Crafts)

Conrad Brooks

Banker / Reporter / Pickup Artist / Bearded Drag (as Connie Brooks)

Henry Bederski

Man with Hat and Receding Hairline (uncredited)

Carol Daugherty

Woman in Nightmare (uncredited)

'Captain' DeZita

The Devil / Glen's Father (uncredited)