Yet another ongoing chase leads Tom & Jerry to the "Space Place" where junior astronauts Buzz Blister & Biff Buzzard are going to undertake a mission to Mars. Causing chaos upon the spaceship, they land on Mars and come across a martian family who warn them of an impending martian attack. Flying back to Earth on a flying saucer they warn everyone of the attack and do manage to stop it but may still see the Earth destroyed by the giant vacuum-wielding "Invince-A-Tron".