The Investigator, a benevolent alien from a distant galaxy, selects an Earth boy and girl, John and Julie, to assist him in his mission to make their world a better place. The pair are miniaturized to assist The Investigator more easily, and assigned to prevent the theft by Stavros Karanti of a 14th-century masterpiece from a church on the island of Malta. John and Julie are presented with a car and a boat, scaled to accommodate their miniaturized size and set out to thwart Karanti's plans...
A planet is discovered in the same orbit as Earth's but is located on the exact opposite side of the sun, making it not visible from Earth. The European Space Exploration Council decide to send American astronaut Glenn Ross and British scientist John Kane via spaceship to explore the other planet.
The International Rescue team is faced with one of its toughest challenges yet, as the revolutionary lighter-than-air craft Skyship One is hijacked while on her maiden voyage around the world. Against backdrops including the Statue of Liberty and the Sphinx, Lady Penelope, Parker, Alan and Tin-Tin fight the hijackers from on-board, while the rest of the team tries to stop the airship crashing.
