After a long flight, the spacecraft Ripley (Sigourney Weaver) took did not fly back to Earth! An accident occurred on the way back to the spacecraft. The cryogenic hibernation module separated from the main ship before the mother ship exploded and fell into a dark and cold planet. Except for the remaining bishop, only Ripley survived. This is an abandoned alien mine on earth, now a prison for dangerous prisoners. Ripley recovered with the help of the doctor. With Ripley's arrival, the prisoners here began to be mysteriously killed one by one...