Consequences regarding Susan's last sent message appear at the Candy Kingdom's shore, bringing about new questions and mysteries leading Finn, Jake and Susan to embark on a new adventure.
After a mysterious craft lands in Ooo, Finn, Jake, Susan Strong, set sail for the Island that it originated, hoping to learn the truth about the past and what happened to the humans.
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.
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.