In the spooky opener of the 22nd annual installment of "Treehouse of Horror," Homer takes a dangerous dive into an isolated canyon on Candy Peak, but when a crashing boulder traps his arm, he channels Aron Ralston to save himself. In "The Diving Bell and Butterball," the first of three hair-raising Halloween tales, a venomous spider bite leaves Homer paralyzed, but when Lisa discovers Homer's ability to communicate through natural gases, he is able to express his love for Marge. The killer spells continue in "Dial D for Diddly," when Ned Flanders, devout preacher by day, transforms into a cold-blooded vigilante by night. In the final terrifying tale, "In the Na'Vi," Bart and Milhouse are assigned on a mission to access a sacred extract on a distant planet. They morph into the land's indigenous one-eyed avatars, but when Bart finds love and an eternal mate abroad, he is caught in planet warfare.