Michael Muhney (born June 12, 1975) is an American actor. Muhney is best known for his role as Sheriff Don Lamb on Veronica Mars, as well as his role as Adam Newman on The Young and the Restless. He is the second adult actor to portray Adam, debuting in the role on June 25, 2009, after Chris Engen left the show. On December 17, 2013, Muhney announced via his official Twitter account that he had been fired from the series. His final episode was aired on January 30, 2014.