Mordecai and Rigby help their favorite '80s sitcom star, RGB2, escape from the studio lot and into the mountains so he can avoid starring in a revival of his show.
When Mordecai and Rigby meet a caveman, they decide to put his unique prehistoric physique to good use: chugging cheese! But could this caveman actually turn out to be a Neanderthal nuisance?
Muscle Man, Rigby and Starla are annoyed about Mordecai's awkward goodbye to Margaret so they try to get Mordecai to tell Margaret how he feels about her.
Benson eats a magical, deadly sandwich that Mordecai and Rigby bought, so the trio must travel with the restaurant's manager, Sensei, to find the cure.
After Mordecai, Rigby and Muscle Man squander the fireworks that Benson had purchased for an upcoming event at the park, the three have to go and find more to replace them before Benson blows a fuse and they lose their jobs.
It’s Margaret’s last night of freedom before she transfers to a new college. So Mordecai, Rigby and Eileen decide to surprise her with the biggest party of her life. What could possibly go wrong?
The house is decorated, the guests have arrived and it seems like it's the season to save Christmas when the gang finds themselves faced with the task of destroying a present for Santa that has the potential to destroy them and the holiday.
Rigby has never been known for his upper-body strength, so when the park employees have to go into the doctor and get their physicals, Rigby has trouble doing even one pull up, and so he must find a way to do so or get fired.