Sonido

• W.L. Trytel — original music composer

Guion

• H. Fowler Mear — screenplay
• Cyril Campion — screenplay
• Heinrich Fraenkel — adaptation
• Alice Campbell — novel

Producción

• Julius Hagen — producer
• Edward L. Alperson — executive producer

Reparto

• Boris Karloff — Dr. Victor Sartorius
• Joan Wyndham — Eve Rowe
• Arthur Margetson — Roger Clifford
• Mona Goya — Yvonne Clifford
• Anthony Ireland — Capt. Arthur Halliday
• Morton Selten — Sir Charles Clifford
• Nina Boucicault — Mary Clifford
• Gibb McLaughlin — Jacques
• J.H. Roberts — Chalmers
• Victor Rietti — Doctor Bousquet
• Wilfrid Caithness — Morrocan Official

Montaje

• Michael C. Chorlton — editor

Arte

• James A. Carter — art direction

Cámara

• Sydney Blythe — director of photography
• William Luff — director of photography

Dirección

• Henry Edwards — director