Patrick Galen Dempsey (born January 13, 1966) is an American actor. He is best known for his work on the television series Grey's Anatomy as Doctor Derek Shepherd. He has won a Screen Actors Guild Award as a cast member of Grey's Anatomy. He has also been nominated for the Emmy and Golden Globe Awards. He has been in the many movies. These include Transformers: Dark of the Moon, Valentine's Day, Sweet Home Alabama, Brother Bear 2 and Enchanted.