Russell Brand caught the 'Tonight Show' audience -- and Jimmy Fallon himself! -- off-guard when he kept launching into rants during a game of Word Sneak last night (Nov. 18).

The game traditionally calls for both players to try and maintain a normal conversation while each working in a list of words. Russell, however, seemed confused by the rules and proceeded to recite a series of monologues, each containing one word on his list. While the speeches were entertaining (we seriously can't believe how much detail he described off the top of his head!), he bent the rules of the game, just slightly. For instance, when it was Jimmy's turn to respond, Russell kept trying to guess the word that Jimmy pulled from his list.

If there's one thing that Russell is known for, it's his off-beat, always unexpected sense of humor. He might not have played the game exactly by the rules, but he had the audience and Jimmy in stitches.

Watch Russell Brand and Jimmy Fallon play Word Sneak in the video above!

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