Is that really 300 hunk Gerard Butler?

The 41-year-old Scotsman appeared strikingly thinner Tuesday as he posed backstage at the Diesel Black Gold Fashion Show during Mercedes-Benz Fashion Week in New York City.

The actor -- whose weight has gone up-and-down over the years -- has reportedly slimmed down for his role in Mavericks, the true story of soul surfer Jay Moriarty.

In the film, Butler plays the mentor to Moriarty, who died at age 23 in 2001 from an apparent free-diving accident.