This classic blend of science-fiction and horror belies its extremely low budget with buckets of atmosphere and some genuinely creepy setpieces. The story concerns the crews of two spaceships, who land on a foggy, seemingly deserted planet. What they don't know is that the planet was home to a race of vampiric aliens, who possess their minds, eventually rising from their strange, misty graves to seek human blood. Legendary director Mario Bava once again proves himself a master at atmospheric composition, using color, sound, and minimalistic sets in original and unnerving ways. Barry Sullivan stars with Angel Aranda and Brazilian actress Norma Bengell. The American version, running several minutes shorter than the original, was put together by Ib Melchior (The Angry Red Planet).
~ Robert Firsching, All Movie Guide