The final installment finds Marty digging the trusty DeLorean out of a mineshaft and looking for Doc in the Wild West of 1885. But when their time machine breaks down, the travelers are stranded in a land of spurs. More problems arise when Doc falls for pretty schoolteacher Clara Clayton, and Marty tangles with Buford Tannen.

A research team in Antarctica is hunted by a shape-shifting alien that assumes the appearance of its victims.

A simple-minded gardener named Chance has spent all his life in the Washington D.C. house of an old man. When the man dies, Chance is put out on the street with no knowledge of the world except what he has learned from television.

A significantly deformed but highly intelligent teenage boy and his biker gang mother attempt to live as normal a life as possible under the circumstances.

Hollywood, 1930s. Tod Hackett, a young painter who tries to make his way as an art director in the lurid world of film industry, gets infatuated with his neighbor Faye Greener, an aspiring actress who prefers the life that Homer Simpson, a lone accountant, can offer her.

When a dispute occurs between a logging operation and a nearby Native American tribe, Dr. Robert Verne and his wife, Maggie, are sent in to mediate. Chief John Hawks insists the loggers are poisoning the water supply, and, though company man Isley denies it, the Vernes can't ignore the strangely mutated wildlife roaming the woods. Robert captures a bear cub for testing and soon finds himself the target of an angry mutant grizzly.

Dr. Bock, the chief of medicine at a Manhattan hospital, is suicidal after the collapse of his personal life. When an intern is found dead in a hospital bed, it appears to Bock to be a case of unforgivable malpractice. Hours later, another doctor, who happens to be responsible for another case of malpractice, is found dead. Despondent, Bock finds himself drawn to Barbara, the daughter of a comatose missionary.

A mysterious preacher protects a humble prospector village from a greedy mining company trying to encroach on their land.

An accident occurs in an ultra-secret government biological weapons laboratory spreading a sinister bacteria.

As the result of a head injury, brilliant computer scientist Harry Benson begins to experience violent seizures. In an attempt to control the seizures, Benson undergoes a new surgical procedure in which a microcomputer is inserted into his brain. The procedure is not entirely successful.