Neil Patrick Harris Pranked 'The Voice' Coaches and It Was a Truly Terrifying Experience For Him

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Now we know what spooks Neil Patrick Harris!

Neil talked to ET about his new show, Best Time Ever, where among other things, the 42-year-old actor pranks unsuspecting celebrities. And he admits that while doing the show is pretty much "a party," pulling one over on say, The Voice judges, can be pretty scary!

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"I was Jurgen Vulmer, who was the host of The Voice Austria, which doesn't exist," he said, explaining the prank, saying that he basically asked the judges a bunch of random, strange questions. "I had almost three hours of prosthetic makeup on. I looked nothing like myself, and had a different accent."

"It was incredibly terrifying," he continued. "They thought I was insane."

With regards to his new show, Neil said he recognizes a changing TV landscape, where you no longer have to be at home, at a certain time, to watch a program, and hopes Best Time Ever alters peoples viewing habits.

"What's fun about our show is if you commit to watching a show, you're a part of the group," he said. "If you're in the theater, you might be in the show. If you're watching at home, you may be on the show."

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Neil should do a great job hosting after his string of awards show hosting gigs, including the Oscars, Emmys, and the Tony Awards. The How I Met Your Mother star opened up about the balancing act that presents someone with.

"The job is just multi-leveled," he said. "You have to entertain. You have to honor. And now you sort of have to educate. To do all of that in the short little time frame that you have between acceptance speeches is a tricky conceit."

Well, you seem to knock it out of the park each and every time, Neil!

Best Time Ever
premieres tonight on NBC at 10/9 c.

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Watch NPH spill his celebrity crush (Sorry, David Burtka!) below.