Emma Stone is a great lip syncher, but a liar, not so much.
The Birdman or The Unexpected Virtue of Ignorance actress showed up on Tuesday's Tonight Show and agreed to play a game of "Box of Lies" with host Jimmy Fallon -- but her poker face wasn't so good.
VIDEO: Top 5 Favorite Jimmy Fallon Lip Sync Battles You Gotta Watch
How the game works is both players must take turns trying to stump each other about what item is hidden inside their mystery boxes. In an attempt to fool Fallon, Stone lied about the Frozen DVD that was cleverly frozen in an ice cube in front of her. Fallon was quick to call her bluff, and earned a point for himself.
When it was The Tonight Show host's turn to pick a box, he too lied and told Stone he had a tiny squirrel surfing a bed of lettuce. He really had a fake hand with a wrist watch on it. Yeah, this game gets weird.
PHOTOS: Must-See Star Sightings
Fallon somehow convinced Stone of the surfing squirrel and in turn won the game.
The 25-year-old actress isn't the first celebrity to play "Box of Lies." Kate Hudson, Kerry Washington and Jennifer Lawrence have also all taken the challenge.
Check out the power of Fallon and his star-studded Tonight Show moments, below.