When Billy is sent to bed after playing with his Dr. Brainiac action figure, he wishes he had an adventure. Then, he notices a strange light outside and wanders into a corn field to investigate; there, he encounters Sperg, and they are both abducted by aliens who experiment with them. Later, when they return home, it is revealed that Sperg has a bomb implanted in his head, and also that there is a shortage of dairy products; Billy explains that the aliens are stealing Earth's dairy products because they are werewolf-like creatures who need cheese, and they have already mined all the cheese in the Moon. In the following, Billy's crazy story is confirmed when too many UFOs appear. Then, Billy says they must assemble a team of diary superheroes, the Green Squeaker (Billy), Milk Mandy, the Cheese Reaper, and Diary Boy (Sperg), to combat the aliens, but everybody is opposed to the idea. Later, the four of them have been captured and are sent to the Moon to be destroyed, but they escape and try to stop the Moon ship from getting to Earth. At that time, the Moon aliens start their transformation into werewolves, and they bite Billy, who becomes a werewolf too. With their backs to the wall, Grim finally chooses to give Billy, Mandy and himself their dairy superpowers. Meanwhile, Sperg sacrifices himself by letting the bomb in his head explode in the control room, thus crashing the spaceship in the Moon and saving Earth. A final segment shows what happened to Billy, Mandy, Grim, Sperg, Dr. Brainiac, and even the Moon people, that remain attempting to destroy the humans by extracting their brains to steal their knowledge after they discussed and revealed their master plan to escape with Endsville's supply of cheese while showing images of the characters from the other shows in the the crossover Cartoon Network Invaded which meant that they were the masterminds behind the entire event. This was the fifth and final chapter of Cartoon Network Invaded which also concluded with an alternate ending on June 1.