(Cover) - EN Showbiz - Patrick Dempsey "loved every minute of" filming Transformers: Dark of the Moon with director Michael Bay and co-star Shia LaBeouf.

The 45-year-old actor is usually occupied with making women's hearts swoon on the television show Grey's Anatomy. Patrick's move to the hard action silver screen was great fun for the heartthrob.

"I'd never been involved with anything quite like it and loved every minute of it," Patrick told Parade magazine. "I had probably the most fun I've ever had on a movie."

Patrick also thoroughly enjoyed working with Shia LaBeouf. The two friends conversed several times on set and Patrick became a bit of a mentor to Shia while filming. Patrick has a high opinion of the young actor.

"I think [Shia's] becoming a man. He's had to learn about himself in a very public way, and fame is very much a double-edged sword," said Patrick. "There's a lot of good that comes with it and there's a lot of negative that comes with it, and I think he's really aware of his strengths and his weaknesses and what he wants to do to improve."

Patrick also has a high opinion of the movie.

"I think this is probably the biggest movie [Michael Bay's] done to date in many ways," said Patrick. "I couldn't believe the size of the production and the scale of what I was involved with."

Transformers: Dark of the Moon is now in theatres. (C) Cover Media