In order to get high school credits, Rigby has to pass a foreign language class taught by Benson in China.

Rigby's high school nemesis returns and tries to stop him from graduating from high school by making sure he fails gym class.

Rigby must borrow his dad's car and return it unnoticed so he can drive Eileen to his school prom.

Rigby must write a speech for his high school graduation that will be broadcast on national TV. Meanwhile, Mordecai sinks into a depression over how Rigby is now more successful than he is, and the park workers finally find out the true intentions of the dome experiment.