The hilarious game is a recurring segment on Fallon's Tonight Show, where guests and Fallon himself have to tell their opponent what's in their box and be judged for their truthfulness.
Mom-of one Washington, who opted to tell the truth for her first go, got a fit of the giggles as she honestly proclaimed to Fallon that she had a pumpkin in front of her, full of spaghetti.
And the Scandal star proved herself to be a good interrogator as she picked apart Fallon's lie when he later tried to deceive her.
Click on the link above to watch Washington's hilarious attempt!
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