Moonbase Alpha is caught in a time- warp and lands on Earth 40,000 years ago where Koenig and his crew encounter themselves as Cro Magnon cave dwellers.
When a seven man landing party fails to return from a newly discovered planet, their Eagle is brought back to the moon by remote control and found to be empty except for the body of a Stone Age man. Commander Koenig (Martin Landau) leads a rescue party which includes Dr. Helena Russell (Barbara Bain), Sandra Benes (Zienia Merton) and Alan Carter (Nick Tate). Koenig and Russell are separated from the others and Sandra is kidnapped by cavemen who take her to a vast cave. There the Chief takes an immediate interest in her, and a fight breaks out over the new prize. She manages to smash a stone against the Cave Chief's head and as he lays dying, tended by his mate, their resemblance to Koenig and Russell is incredible!
Meanwhile, Professor Bergman (Barry Morse) and Kano (Clifton Jones) have followed in another Eagle and together with Carter they discover Koenig lying unconscious, his face covered with dried blood. He is taken back to Moonbase Alpha, where results of the tests on the dead caveman in the earlier Eagle confirm that he belongs to the Cro Magnon period of 40,000 years back in time. Yet his teeth are capped and finger and blood tests prove him to be the pilot of the first reconnaissance flight!
Koenig regains consciousness and realizes he has been through a time warp, and co-existed as the Cave Chief. Helena, now the Cave Wife, and other cave people who are actually Moonbase Alpha personnel, are all facing death, for Carter has set out to find Sandra, ready to kill with his deadly ray gun. If he does, his victims will be Helena and his own comrades.
MARTIN LANDAU as John Koenig
BARBARA BAIN as Dr. Helena Russell
BARRY MORSE as Professor Bergman
Prentis Hancock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Paul Morrow
Clifton Jones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . David Kano
Zienia Merton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sandra Benes
Anton Phillips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dr. Mathias
Nick Tate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Alan Carter
Oliver Cotton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Spearman
Producer: Sylvia Anderson Executive Producer: Gerry Anderson Screenplay by: Jesse Lasky, Jr.
and Pat Silver
Story Consultant: Christopher Penfold Moon City Costumes Designed by: Rudi Gernreich
Directed by: Bob Kellett Series Created by: Gerry and Sylvia Anderson
Color/Approx. Running Time: 52 Minutes
When a planet is discovered approximating Earth's environment, Moonbase Alpha personnel prepare for an exodus... but the alien world is not what it seems to be.
The runaway moon encounters a new solar system and in it a planet Professor Bergman (Barry Morse) identifies as Ariel. If the moon can establish an orbit around it, the gravity will approximate that of the original Earth-Moon relationship, and hopes arise that they have found a compatible planet. Fears that an alien attack is being made are assuaged when a satellite- shaped object lands, pouring out a gas which creates fresh air. On the horizon: the long-forgotten sight of blue sky and a warm sun!
Commander Koenig (Martin Landau) and Dr. Russell (Barbara Bain) run every check on the new planet in preparation for an exodus. For Paul Morrow (Prentis Hancock) and Sandra Benes (Zienia Merton) in particular, there is the joy of a future with a home of their own and children.
But a violent storm shakes the moon. Off base, on a reconnaissance mission in an Eagle, Helena, Paul, Sandra and their pilot, Alan Carter (Nick Tate) are caught in the turbulence and crash. Sandra is injured and their water supply is contaminated. Paul finds a white substance which slakes his thirst and carries Sandra to a place where he builds a hut. However, Helena and Alan realize that Paul's mind has been affected by whatever it was he tasted, and hopes of their being found by searchers from Moonbase Alpha recede. The future is not what it had seemed to be - and from the planet Ariel there is at last a verbal communication which confirms this.
MARTIN LANDAU as John Koenig
BARBARA BAIN as Dr. Helena Russell
BARRY MORSE as Professor Bergman
Prentis Hancock . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Paul Morrow
Clifton Jones . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . David Kano
Zienia Merton . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Sandra Benes
Anton Phillips . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Dr. Mathias
Nick Tate . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Alan Carter
Producer: Sylvia Anderson Executive Producer: Gerry Anderson Screenplay by: Christopher Penfold
Moon City Costumes Designed by: Rudi Gernreich
Directed by: Charles Crichton Series Created by: Gerry and Sylvia Anderson
Color/Approx. Running TIme: 52 Minutes
Copyright Martin Willey. Thanks to James Poll.