Did Maisie Williams Run Off 'Tonight Show' Set After Letting Slip Major 'Game of Thrones' Spoiler?

Maisie Williams turned white as a sheet and clasped her hands to her mouth after she said one sentence on "The Tonight Show" Monday night about the final season of "Game of Thrones."

Jimmy Fallon had been provoking her to say one thing, just drop one morsel of a teaser about what's to come in the final episodes of the HBO blockbuster fantasy series, and so she relented, talking about the final days of filming.

We won't spoil what she says here, but her expression and reaction afterward says it all as she panics, freaks out and starts to ask if Jimmy can edit it out. She even got paranoid that the audience was going to start tweeting out her words before finally she upped and fled the set.

Let's just say it may have been the best April Fool's Day joke of the day, and one of the best of all time. And Williams was absolutely stellar selling that moment after she let slip the so-called "spoiler."

Honestly, it's not even worth writing what she said here for two reasons. One, it's obviously not true. But more importantly, it's so worth seeing how she acts her way through the revelation, the realization and the aftermath. If it's possible to win an Emmy for a talk show appearance, this would have to be up for consideration.

Fallon did a capable job of playing along -- he's gotten a lot better in this area -- but it was Maisie Williams who sold it so compellingly that even as you just knew this was a prank, there was a part of you wondering ... what if it's not?

Kudos to Williams and Fallon for pulling off such an epic prank. And we can't wait to see what happens to Arya Stark in the final episodes. And if it is somehow what Williams said, well then they got us even better than we realized.

The final season of "Game of Thrones" premieres Sunday, April 14 at 9 p.m. ET on HBO.

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