(Cover) - EN Showbiz - Patrick Dempsey worries Grey's Anatomy will begin "playing the same beat" again and again.

The actor is known for his portrayal of Dr. Derek McDreamy' Shepherd in the American medical drama. Earlier this year he sparked concern among fans by saying the upcoming eighth season would be his last during an interview, but he later released a statement explaining he hadn't meant the comments to sound so definite.

Patrick is playing his cards close to his chest when it comes to the role, admitting he wonders how long the programme can go on for and still stay relevant.

"After 150 episodes, it's very easy to repeat one's self, and I hope we can move forward with these characters so we're not playing the same beat over and over," he told the LA Times. "That is my concern. It's really important that you move forward with the relationships and the fans realise what's happening and where [the relationships] need to go, and they are very smart. The loyal fans who have been with us since day one want to see these characters grow up and not stuck in an adolescent dynamic."

Patrick appears in this summer's blockbuster Transformers: Dark of the Moon, playing villain Dylan. He was thrilled to get the part as it was such a change for him, admitting he loved being able to show he isn't just "mister-weepy-doctor guy".

Also enjoyable were the new fans the role attracted. Patrick is an avid racing-car driver, and was thrilled when men at a recent meeting singled his portrayal out for praise.

"I've been known for this one role and for making these light movies," he explained. "Those were the opportunities I had and the movie I had to make. But now I just got back from a race this past weekend, and all the guys in the paddock where like, 'Hey, I went to Transformers it was good to see you in a movie like that.' It was nice to see them excited." (C) Cover Media