'Robert to the Rescue' by Dennis Spooner

A huge orbiting space station causes confusion at Space City when Professor Matic mistakes it for a new planet. Steve Zodiac and his crew set off in Fireball XL5 to investigate, but when they head down to the structure’s surface in Fireball Junior they are captured by two aliens, Magar and Proton, who announce that they will wipe the humans’ memories and then keep them there forever. But before his brainwashing begins Steve manages to order Robert to rescue them...

Paul Maxwell (Colonel Steve Zodiac), Sylvia Anderson (Doctor Venus), David Graham (Professor Matt Matic / Lieutenant 90 / Zoony the Lazoon / Magar), John Bluthal (Commander Zero / Proton), Gerry Anderson (Robert the Robot)

Directed by Bill Harris
Produced by Gerry Anderson
Associate Producer Reg Hill

TX (UK - ITV):
12th August 1963

Notes:
*Featuring Colonel Steve Zodiac, Venus, Professor Matt Matic, Commander Zero, Lieutenant 90 and Robert the Robot