Fireball XL5

Fireball XL5 intercepts a missile sent to destroy Earth. While doing so they are captured by the Subterrains -who launch a second missile, with Venus on board!

A flying saucer leads to the crew attempting to save a planet which has broken out of its orbit and is on a collision course with another planet.

The Mayflower III, piloted by Venus, is carrying pioneers to a new planet. But the indigenous Lillispatians have objections to their world being colonized.

Prof. Matic's old friend, Dr. Rootes, attempts to conquer Earth using an invasive species of alien plant life, which immediately runs amok.

Fireball XL-9 is attacked by a mysterious ship so XL-5 replaces it on patrol. Steve heads to the nearest refueling station , but the crew find it deserted except for Boris and Griselda Space Spy, who plan to steal XL-5.

On Rejusca, Steve and Zoonie must rescue Venus from sun worshippers who intend to make a sacrifice of her to their solar deity.