After the events of "Rigby's Graduation Day Special" the Park crew and Eileen must formulate a plan to survive in space.
The crew have an encounter with "brobots" whose purpose is to serve others, but Mordecai and Rigby are suspicious of them.
After learning their true mission in space, the crew is excited to make history, but Benson still wants to return home.
Mordecai and Rigby volunteer to rescue a scientist's husband in exchange to earn space creds so that they can buy hover shoes.
Chance Sureshot loses his wallet and is enclosed in a robot's bubble until he can pay for his food. In order to free him, Mordecai, Rigby, Toothpick Sally and Recap Robot must travel to the Mantis Planet to get it back.
Muscle Man sets out to prank someone.
The guys try to help Pops overcome his nightmares.
Mordecai and Rigby must stop an evil brain after Rigby releases it from a cage.
Benson hunts for some fries.
Rigby must pass the Space Tree Safety Test.
Mordecai and Rigby are on trial for an incident that happened downtown.
Mordecai and Rigby get pumped to see a rock concert on the spaceship.
The guys race through space.
Mordecai and Rigby try to avoid spoilers about their favourite TV show.
The guys must escape a bad guy.
The guys screw around with a teleportation machine.
The guys engage in confrontations.
The gang tells scary stories with a science fiction twist.
The guys have to play a special VHS tape.
The guys have a super important lesson.
The guys help Pops' train.
The guys celebrate their first Christmas in space by sharing stories and opening presents, but Benson gets annoyed that the stories have scary elements.
Pops wants to be friends with Anti-Pops.
The guys need to talk to someone smart.
The guys try to cheer up Pops for his upcoming fight.
In the epic series finale, the fate of the universe will be decided.
Allies from both sides rally together for the epic fight. However, Pops and Anti-Pops are once again at a stalemate. Mordecai and Rigby are forced to jump between the two factions.
Mordecai and Rigby relive the first episode, but soon realize that they need to help Pops. Pops realizes that he must reach out to Anti-Pops and finally saves the universe at the cost of his life. The entire park crew return home to their friends and family where they are seen growing up and moving on to better lives. 25 years later, the entire crew return and Mordecai and Rigby reflect on Pops' sacrifice. Regular Show ends with Pops watching the series on VHS and uttering one final, "Jolly Good Show."