LEGO NEXO Knights season 1 episode 1
Episode title: The Book of Monsters Part 1
During the graduation ceremony for the new Knights of Knighton, Jestro the jester is ridiculed for his terrible, uh, jestring. Distraught, he's seduced by the powerful and evil Book of Monsters until Merlok the Magician tries to stop Jestro by using his most powerful magic spell.
