Finn and Princess Bubblegum try to avert a zombie apocalypse, Jake comes down with the lumps, and the Ice King thinks he may have found a potential bride.
Marceline reconnects with her estranged father, Finn and Jake are kept awake by a horse, and the Ice King develops a new look.
Finn and Jake meet the evil Cute King, they become trapped in an arena of gladiator ghosts, and venture into Marceline's mind to save her.
Finn develops a crush on Flame Princess, Tree Trunks is courted by Pig, and Jake thinks a bear is trying to steal Finn's identity.
Finn and Jake chase the Lich through a portal, a game of catch goes awry, and Lady Rainicorn gives birth to five puppies.
Finn and Jake try to commit a cosmic crime so that they can access a multiverse prison called the Citadel, they find Finn's father and Princess Bubblegum orders the arrest of the Jameses.