'The Ghosts of Space' by Alan Fennell

The crew of Fireball XL5 are assigned to take a geologist named Frazer to the remote planet of Electron. However, when they arrive on the planet, they are surprised to find it deserted. After Steve Zodiac and the rest of the XL5 crew leaves, Fraser spends the night in a deserted ghost town, where he discovers a strange, glowing electric rock. Over the next few months Frazer amasses tons of electric rocks, but when Steve eventually returns in Fireball XL5 he refuses to take the consignment back to Space City, as the rocks are too heavy to make lift off. Frazer is furious, and threatens Steve to make him change his mind by morning. Meanwhile, two aliens have arrived on Electron for their regular supply of electric rocks – on seeing Fraser and the others they decide to scare them off using the same method they used to frighten all the planet’s previous inhabitants…

Paul Maxwell (Colonel Steve Zodiac), Sylvia Anderson (Doctor Venus), David Graham (Professor Matt Matic / Zoony the Lazoon / Senta), John Bluthal (James Frazer / Halla), Gerry Anderson (Robert the Robot)

Directed by John Kelly
Produced by Gerry Anderson
Associate Producer Reg Hill

TX (UK - ITV):
25th November 1963

Notes:
*Featuring Colonel Steve Zodiac, Venus, Professor Matt Matic and Robert the Robot