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 exclusively told BANG Showbiz: ''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.''