During the journey home from their sea-faring adventure; Finn, Jake, and BMO encounter a mysterious force that enters their dreams.

Finn, Jake, and BMO return from their voyage to a radically changed Ooo.

The friends learn the story of what happened to Ooo, while Betty continues her attempt to reach Simon, but she's interrupted by someone out to steal her magic.

Finn, Jake and Ice King break into the Ice World to confront the power-hungry evildoer responsible for the chaos in Ooo and try to rescue Betty.

After taking a nap, Finn and Jake get separated from Betty and the Ice King. They need to get back and Jake needs to go pee.

In order to save Ooo, Finn and Jake must gather the four elemental gems. They go to the Slime Kingdom and have to gather Slime Princess's gem.

After gathering the Slime jewel, Finn and LSP go to the Fire Kingdom, to gather the Flame Jewel. Everything has turned even hotter than before.

After going to the Fire Kingdom, Finn becomes taken over by fire. LSP has to save him before he destroys the candy kingdom.

After saving Finn the human during a battle between the candy kingdom and the fire kingdom it is discovered that LSP is made of anti-elemental magic and restores Ooo to it's former state.

Jake struggles through the personal changes happening to him as a mysterious encounter in a dream with his brother Jermaine begins to haunt him.

BMO and Marceline play catch up on recent events.

While performing a reading of 'Fiona and Cake', Ice King is confronted by a familiar figure.

While safeguarding a frightened Sweet P, Finn is led into a confrontation with an old foe.

Finn and Fern's carefree visit to some old ruins turns disastrous.