'Space Pen' by Dennis Spooner

Posing as the crew of space ship 2X4, Mr. and Mrs. Space Spy land at Space City, steal some radioactive isotopes, break into Steve Zodiac’s personal vault, and then make their escape. Steve and Commander Zero hatch a plan to catch the villains: pretending to be pirates who have stolen Fireball XL5, Steve and his crew follow the spys back to the planet Conva – but the plan misfires, and they find themselves prisoners in a deadly water chamber trap…

Paul Maxwell (Colonel Steve Zodiac / General Shan), Sylvia Anderson (Doctor Venus / Griselda Space Spy), David Graham (Professor Matt Matic / Lieutenant 90 / Zoony the Lazoon / Boris Space Spy / Caramachi), John Bluthal (Commander Zero / Al), Gerry Anderson (Robert the Robot)

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

TX (UK - ITV):
27th May 1963

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