Daniel Radcliffe Can't Stop Laughing During 'Water War' With Jimmy Fallon

Someone must've hit him with a giggling charm.

Hopefully Harry Potter brought his gillyweed.

"Victor Frankenstein" star Daniel Radcliffe took on Jimmy Fallon in a "Water War" on Tuesday, and he just couldn't keep it together. Radcliffe started laughing almost immediately, and once he got to dump water on Fallon, he pretty much didn't stop. 

Radcliffe played a wizard for most of his childhood, so he's used to doing pretty amazing things. Once he shocked people by pretending he was the receptionist at Nylon magazine, and during a previous visit on "The Tonight Show," he expertly rapped the "Alphabet Aerobics." But that stuff aside, seeing Harry Potter apparently get hit by a giggling charm is just as magical as anything.

"The Tonight Show Starring Jimmy Fallon" airs weeknights at 11:35 p.m. ET on NBC.

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