Maisie Williams deserves to be in contention for another Emmy nomination this year — if not for her turn as the needle-slinging assassin Arya Stark on Game of Thrones, then at least for this all-too-convincing April Fools' Day prank she pulled on The Tonight Show with Jimmy Fallon.

While promoting the show's upcoming Season 8 premiere, Williams tossed out the increasingly generic cast line: Details about the HBO epic's final run are being kept so close to the chest that there's very little she can say about the half dozen episodes ahead. But then, when pressed by Fallon to share at least a tiny hint for audiences at home, she dropped the motherload.

Here's the Game of Thrones Season Maisie Williams Thinks Fans Should Revisit Ahead of Season 8

"During shooting, the final days were really emotional saying goodbye to all of the cast," Williams began, "because when I found out that Arya died in like the second episode, I was..." At that, her eyes bugged out, her hands snapped across her mouth, and she searched the sound stage for a friendly face that could assure her she did not just do what she thought she just did.

With the look of terror only a potential contractual violation with HBO could inspire — the results of which would probably make Arya Stark's kill list look PG — she then asked Fallon if her segment was airing live or if they could re-shoot their exchange to remove her spoiler slip. Looking distraught, Williams rushed off the stage in a panic. After Fallon went behind the curtains to retrieve her, the two jumped out with big grins to reveal that it was, indeed, all a joke, but she definitely had us going there for a minute. Looks like there's no need to worry about Williams' longevity post-GoT because a girl apparently does have many faces.

Game of Thrones Season 8 premieres on Sunday, April 14 at 9/8c on HBO.

PHOTOS: Game of Thrones Season 8

Maisie Williams as Arya Stark, <a href=""><em>Game of Thrones</em></a>Maisie Williams as Arya Stark, Game of Thrones