Every little thing he does is magic.
Harry Potter's Daniel Radcliffe made a surprise appearance at the end of Jimmy Fallon's monologue on The Tonight Show Tuesday. Fallon began the bit by telling a joke to the studio audience: "South Korea is building a giant monument to the song 'Gangnam Style,' which will feature two overlapping wrists, a signature move of the 'Gangnam Style' dance," the host said.
"Hey, Jimmy, sorry to interrupt, but you're about to do it right?" a man asked.
"About to do what?" Fallon asked.
"Come on, you know what!" the man said. "'Oppa Gangnam Style.'"
"Oh, no. I'm not going to do the 'Gangnam Style' dance," Fallon said. The man protested, saying, "Oh, come on! Why else would you even mention it? You can't set the table and not serve dinner." Fallon responded to the heckler by saying, "Sorry to burst your bubble here, but I was just going to tell a joke about that story."
"You know what would be a joke? If you didn't do 'Gangnam Style.' Now, go on, Jimmy! Do the dance," the man said. "America's waiting. Aren't we?" As the audience cheered loudly, Fallon shouted, "No! No! Stop it! I'm not gonna do the...Stop it! No! I'm not going to do the dance."
Another audience member commanded Fallon to "do the 'Gangnam Style' dance."
"You can't command me to do anything," Fallon said.
"That's a good point," the audience member admitted. "I'm sorry."
Then, a familiar voice appeared from the side of the stage: "You will do that dance."
"Excuse me?" Fallon asked.
"You will do that dance," the man reiterated.
The camera cut to Victor Frankenstein's Radcliffe, who then said, "Now, listen to me, James Fallon: I didn't swim here all the way from England not watch you not do the 'Gangly Style' dance, OK? Hit the music." Fallon obliged and did the dance PSY made famous in 2012. "There!" he said. "Are you happy?"
"Eh," Radcliffe replied. "It wasn't as good as I imagined it would be."
Later in the show, they faced off in a twist on the card game War called "Water War." Whoever lost a round would get pint of water thrown in his face. "People can play this at home. They have. It's a very fun game for the family to gather around Thanksgiving. Someone should play this outdoors—or indoors. I don't make the rules. You make your own house rules," Fallon said.
The first person to throw five glasses of water on his opponent won the right to use a water cannon on the loser. To see who won and who got soaked, watch the clip.
(E! and NBC are both members of the NBCUniversal family.)