Capricorn One—the first crewed mission to Mars—is on the launch pad. Just before liftoff, astronauts Charles Brubaker, Peter Willis, and John Walker are suddenly removed from the spacecraft. Bewildered, they are flown to an abandoned military base in the desert. The launch proceeds on schedule, with the public unaware the spacecraft is empty.
At the base, NASA official Kelloway informs the astronauts that a faulty life-support system would have killed them in-flight. He says they must help counterfeit the televised footage during the flight to and from Mars. Another failed space mission would result in NASA’s funding being cut and private contractors losing millions in profits. Kelloway threatens their families to force their cooperation.
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At the beginning, you can see James Brolin, Hal Holbrook, and O. J. Simpson.