Troy and Phones rescue an unconscious man who wakes up and uses a mysterious device to hypnotise everyone in Marineville.

Captain Thrice embarks upon a mission to find the legendary Lavender Castle, the greatest source of power in the universe, before the evil Dr. Agon can destroy it. In search of a crew for the starship Paradox, he sets out to rescue the prisoners of the wicked space pirate Short Fred Ledd, but finds the pirate in league with Dr. Agon.

Joe takes the place of an injured test pilot to demonstrate a new hypersonic fighter aircraft, only to find himself in mortal danger.

Torchy stumbles upon the King of Topsy Turvy Land, who offers the lad a tube of cardboard to repair his rocket. Unfortunately, King Dithers gets rolled up in the tube, and Torchy has to figure out a way to get him out.

Zero-X lands on Mars, where the crew encounters alien life in the form of the deadly rock snakes, before returning to Earth. When disaster strikes again and the ship is doomed to another crash landing, International Rescue face a race against time to save the crew!

International Rescue are asked to protect the Zero-X Mk II, humanity's first manned mission to Mars, from further sabotage attempts after the Hood accidentally destroys the Mk I on its maiden flight.

An alien spacecraft crashlands on the Moon, its passengers refugees from a dying world. As their destination is Earth, they generously offer to take one person with them when they depart. The scheming Commissioner Simmonds takes steps to ensure that he is the lucky individual chosen, even if it means destroying Alpha.

A staffed, pirate telecommunications satellite (which broadcasts a music programme of which Tin-Tin is a devoted fan) is disrupted by the detonation of a rogue unmanned space rocket and is set on collision course with a Middle Eastern oil refinery.

Posing as criminals, the XL5 crew head for the prison planet Conva in pursuit of two Space City raiders, only to end up in Mr and Mrs Space Spy's lethal water chamber.

A flashback episode focusing on SHADO's formation and how it caused the failure of Straker's marriage.