Nervous about giving a speech at Princess Bubblegum's science conference and barbecue, Finn finds a magical pair of glasses that make him the smartest being in the land.
The Lich, the greatest form of pure evil in the land of Ooo, is accidentally unleashed. With the highest stakes, Finn and Jake set out on the most serious adventure of their career.
Finn and Jake ask Marceline the Vampire Queen to turn them into vampires. However, she isn't interested in transforming her friends and tricks them into thinking she has.