Wallace Michael Shawn (born November 12, 1943) is an American actor and playwright. His best-known film roles include Wally Shawn in My Dinner with Andre (1981), Vizzini in The Princess Bride (1987), and Rex the toy dinosaur in the Toy Story animated film series. Shawn also played Grand Nagus Zek in Star Trek: Deep Space Nine.
His plays include The Designated Mourner, Aunt Dan and Lemon, and Grasses of a Thousand Colors. He also co-wrote the screenplay for My Dinner with Andre with Andre Gregory, and scripted Vanya on 42nd Street, a film adaptation of Anton Chekov's play Uncle Vanya.
He voices Rasheeta in the Adventure Time episode "Puhoy."