The moon approaches a star with two life-supporting planets in identical and opposing orbits, neither world ever seeing the other directly. Unexpectedly, a battleship from one of those planets approaches the moon, and Koenig puts Moonbase Alpha on red alert, assuming that the massive vessel’s intent is hostile. But it seems the aliens already have the upper hand – none of the battle-ready Eagles can lift off from the moon. The main computer also shows signs of being influenced from an outside force, and then Alpha’s defense screens and communications fail. Moonbase Alpha is powerless to prevent the battleship from landing and launching missiles – but the base isn’t the target. The aliens are using the moon to launch a vicious attack on the other planet, a target their missiles would normally never reach thanks to the star’s gravity. A counterstrike targets the moon – and before a signal can be sent to either of the warring planets, Moonbase Alpha is a target for both sides in a bitter, centuries-old war to the death.
written by Bob Kellett
directed by Bob Kellett
music by Barry Gray
additional music by Vic Elms
Guest Cast: Caroline Mortimer (Dione), Prentis Hancock (Paul Morrow), Clifton Jones (David Kano), Zienia Merton (Sandra Benes), Nick Tate (Alan Carter), Maxine Audley (Theia), Kevin Stoney (Talos), Carolyn Courage (First girl)
Notes: It wasn’t originally intended to be last, but this episode wound up closing the first season on its first UK broadcast. It was the 18th episode produced.
LogBook entry by Earl Green