Warning: You will not be able to keep a straight face.

With the second season of his hit show "Derek" recently premiering on Netflix, Ricky Gervais stopped by "The Tonight Show" and joined Jimmy Fallon for a game of "Word Sneak." In the game, Fallon and Gervais try to casually work random words into normal conversation, but that is not even close to what actually happens.

Right from the start, no one can keep it together.

Make sure to watch until the end. The whole segment builds to one final moment that is so funny it leaves Gervais in tears and has Fallon literally falling out of his chair.