Barbara Steele said she refused to do a topless scene so the director brought in a body double who was shorter and had much bigger breasts. They just hired the first woman willing to take her clothes off instead of finding someone who matched Steele's physique. Then they put her in a cheap wig and shot a close-up of her bare chest. Steele said the poor woman was excited about being in a movie even though only her breasts were seen.
Also known as "Castle of Terror:". In that " version, Barbara Steele is in the opening credits alongside Georges Rivière.