James McAvoy was a "huge energy ball" while filming 'Filth'.
According to the movie's director, John S. Baird, the 35-year-old actor was always in high spirits on the set of the comedy drama - which was released in 2013 - making him "incredible" to work with.
He said: "James is full of life. He's a huge energy ball. He's actually currently starring in a theatre production called The Ruling Class. He's as good in that as he is in Filth.
"He's just incredible. A ball of momentum and energy and madness. I'd love to work with him again."
The Scottish director added the 'Atonement' star also liked to have a laugh off set and revealed he "clicked" with the Port Glasgow-born actor after getting to know him over a drink.
He explained: "We clicked, we clicked and we're very close. When you've got a few days off, you know, for turnaround and stuff you can get to know him a bit better. We never did it when we were actually shooting. It was always on days off or the weeks off, in between moving countries and stuff."