AllMovie

When contact is established between Earth and the planet Chroma, located ten light years away, an exchange is proposed between inhabitants of the two worlds. This is to be done by matter-transmitter, using technology provided by the Chromoites -- as it is a dangerous experiment, the first Earth subject, Chino Rivera (Henry Silva), is chosen from the ranks of convicts serving life sentences. As it turns out, both Rivera, who is twice as smart and three times more clever than the project director, Dr. Kellander (Michael Higgins), and the Chromoite visitor, a walking, human-sized crustacean, immensely strong, with nasty claw-like appendages and various openings that gulp, suck, and grind, are up to something other than what they're supposed to be doing, possibly involving murder. Rivera is injured in an escape attempt before he can be transmitted and, while recovering, attempts another breakout, only to find himself accused of killing one of the scientists on the project. Only one of his captors, Dr. Julia Harrison (Diana Sands), believes that he is innocent, and suspects that something far more sinister than even murder is taking place.