0305-b What Was Missing

31b "What Was Missing"

A creature known as a Door Lord suddenly intrudes into Finn and Jake's house and he immediately steals something from each of them (Finn has a piece of Princess Bubblegum's hair and Jake has an old blanket from when he was a puppy) along with Beemo's controller. Finn, Jake and Beemo chase after the Door Lord as he throws keys onto the ground or into the air which magically create a door that leads to somewhere else in the Land of Ooo. They quickly encounter Princess Bubblegum and Marceline who join the chase for the Door Lord but they're eventually blocked by a giant door with a message around the frame that says only a "Genuine Band" can open it. Therefore, they form a quartet: Finn beatboxes and sings, Jake plays his viola, Princess Bubblegum plays Beemo as an 8-bitinstrument, and Marceline plays her electric bass guitar. After a number of attempts to create a song that everyone enjoys, Finn figures out that they need to sing a heartfelt and emotional song that reveals the truth to everyone about how it feels to have them as his friends. This song of true friendship manages to open the door and everyone gets their stuff back. It should be noted that Princess Bubblegum and Marceline appear to be enemies for a brief time during this episode but they renew their friendship with each other at the end. 
"http://en.wikipedia.org/wiki/List_of_Adventure_Time_episodes"

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