Maisie Williams stunned The Tonight Show audience into silence on Monday when she pretended to drop a sensational spoiler about Game of Thrones .

Williams, who plays Arya Stark in HBOs hit fantasy drama, casually dropped what she claimed was a devastating detail about her characters fate in the shows eighth and final season during her interview with host Jimmy Fallon .

Her fake reaction to realizing shed dropped the bombshell was award-worthy:

Of course, it was an April Fools prank which Williams and Fallon took great delight in revealing after shed stormed off the set.

Or was it?

The final season of Game of Thrones begins April 14 .

Check out the full clip above.