Beware of ouija boards, vampires and unexpected tricks in the 21st annual "Treehouse of Horror" trilogy. In "Tweenlight," Lisa becomes smitten with mysterious new student Edmund (guest voice Daniel Radcliffe) only to discover he is a vampire. After Lisa and Edmund run away to "Dracula-la Land," Homer must come to the rescue to save her before she becomes one of the undead in the all-new "Treehouse of Horror XXI" episode of THE SIMPSONS airing Sunday, Nov. 7 (8:00-8:30 PM ET/PT) on FOX.

Beware of ouija boards, vampires and unexpected tricks in the 21st annual "Treehouse of Horror" trilogy. In "Tweenlight," Lisa becomes smitten with mysterious new student Edmund (guest voice Daniel Radcliffe) only to discover he is a vampire. After Lisa and Edmund run away to "Dracula-la Land," Homer must come to the rescue to save her before she becomes one of the undead in the all-new "Treehouse of Horror XXI" episode of THE SIMPSONS airing Sunday, Nov. 7 (8:00-8:30 PM ET/PT) on FOX.

And the category is...... #jeopardy  

Daniel Radcliffe (Harry Potter), "Diggs" and "Treehouse of Horror XXI"
One of my favorite lines is in one episode ["The PTA Disbands"], when Lisa makes a perpetual motion machine and Homer comes in and says, "In this house, we obey Newton’s laws of thermodynamics." That’s a brilliant line. Also, any of Troy McClure’s — "I’m Troy McClure and you may recognize me from Alice’s Adventures Through the Windshield Glass," when he’s doing a drivers’ ed video [in "Duffless"]. I can come up with more if you give me time. Right now that’s all I can think of. I love my own episodes. It’s almost so surreal to watch them that I can’t. That was absolutely how I judged fame when I got the job of Harry Potter. The second thought after, "I’m going to play Harry Potter," was, "Maybe I’ll get to be on Simpsons one day." And I did, so I can die happy.

In an episode airing this coming season, Bart will encounter Diggs (Radcliffe), a strange older boy with a passion for falconry, among other things. “Diggs is a combination of Holden Caulfield, Finny from A Separate Peace and the kids in Lord of the Flies — only a little more screwed up,” executive producer Al Jean tells EW.

Why did the producers bring him back? “I had the pleasure of meeting him after one of his performances in How to Succeed in Business Without Really Trying, and he is one of the people who actually listens to Simpsons DVD commentaries,” quips Jean. “Also, he was terrific.”