The Bourne Identity star Matt Damon enjoyed working with Robert De Niro as director in new movie THE GOOD SHEPHERD, except when he was made to mud wrestle - naked. The drama tells the story of the birth of the US Central Intelligence Agency (CIA) thorough the eyes of Damon's character, EDWARD WILSON, and also stars Angelina Jolie and Alec Baldwin. However, while Damon has lavished praise on De Niro for making him a "much better actor", the 26-year-old detested his mud-fighting experience, which was part of his character's initiation process to join an elite college fraternity. He says, "It was cold. It was winter and the big doors we needed to get the equipment in were open. It was demeaning enough to do the wrestling, but then to be all huddles, shivering."