Adventure Time - S01 - Ep 3

Princess Bubblegum sends Finn on his most challenging quest yet--to recover The Enchiridion, the hero's handbook.

Princess Bumblegum's latest experiment accidentally unleashes an undead horde upon the Candy Kingdom.

Finn adventures into a forbidden dungeon, against the wishes of Princess Bumblegum and Jake, and finds more than he bargained for.

Marceline the Vampire Queen tricks Finn into swearing allegiance to her.