Timon is getting picked on by Shenzi, Banzai and Ed, who are using the meerkat as a volleyball. After Banzai throws Timon to a tree, Pumbaa shows up and charges at Banzai, causing the trio to flee.
Timon then tells Pumbaa that he's tired of being picked on by the whole world and then a U.F.O. suddenly comes and abducts Timon and Pumbaa. Timon and Pumbaa are taken to Pluto, where they are introduced to the King and his daughter, who is a beautiful meerkat which Timon has a crush on. The King tells the duo that they have been chosen to compete in his Interstellar Gladiator Games and that they will represent their home planets in their athletic type competition.
Timon and Pumbaa refuse to compete in the gladiator games and try to force them to take them back to Earth, but the King objects, saying that they have to fight since they got chosen. He then states that the winner will get lots of untold wealthiness and power and will also marry the Princess. Hearing the King's words, Timon decides to stay until he and Pumbaa see who their competitors are: vicious aliens.
The King orders the alien guard to take Timon and Pumbaa to the containment quarters, where they are put into birdcages. Pumbaa reads a brochure that talks about Pluto, which states that on this planet, people can easily lift heavy objects, run fast, and jump high. The warthog finds the brochure to be helpful, but Timon tells his friend that it's not for them since they are animals instead of people. The two friends them sob over their fate.
The next day, the competition begins. While Timon and Pumbaa fight off the aliens, they realize that the brochure Pumbaa read earlier was right, as they are able to jump high and lift the giant monsters. They defeat the aliens and therefore win the competition.
Later, Pumbaa begins to feel homesick and wants to leave, but Timon prefers to stay in Pluto with the Princess, leading to the two to have an argument. The scene then cuts to the start of the battle to the death, where Timon and Pumbaa are forced to fight each other. At first, they refuse to fight until Pumbaa makes fun of Timon having a crush on the Princess. While Timon and Pumbaa fight, the Princess is revealed to be an alien in disguise, much to Timon's shock. The meerkat then decides to quit, but then, Pumbaa zaps his friend with his weapon and, from all outward appearances, Timon is presumed dead.
Pumbaa tells the King that he wants to go back to earth to bury Timon and the king accepts the warthog's decision. However, when Timon and Pumbaa get in the U.F.O., they reveal to the King and his daughter that they were faking the whole fight.
When Timon and Pumbaa get back to earth, they find Shenzi, Banzai, and Ed and pick on them by making them repeatedly rise and fall back to the ground with the U.F.O.'s tractor beam. Pumbaa tells Timon that he saw the Princess take off her costume, and Timon tells the warthog that he was going to talk him about it, saying that nobody means more to him than he does as he is the only one he knows who has never picked on him.
This is the seventh and last appearance of Shenzi, Banzai and Ed in the series, and their most recent chronological appearance in the franchise.
The title is a reference to the Warner Bros. movie Space Jam.