Derek Shepherd is a fictional character from the television series Grey's Anatomy. He is portrayed by actor Patrick Dempsey and is known for being a talented neurosurgeon. Derek is often referred to by his nickname, "McDreamy," due to his charming personality and good looks. Throughout the series, he has complex relationships, particularly with fellow surgeon Meredith Grey. Derek's character is introduced in the first season and becomes a central figure in the show's narrative. He faces various personal and professional challenges, including his tumultuous marriage to Addison Montgomery and his struggles with the demands of his career. His character's journey explores themes of love, loss, and the pursuit of happiness.