The Braveheart director admits The Matrix star Weaving couldn't always be on set for Hacksaw Ridge, and so Mel had to use a little shadow play.

"My shadow is in it and my arm is in it," he tells WENN. "I said to Hugo, 'Come do this film and then his scheduling was such that he couldn't do the scene in the courtroom, so I did it.

"There's my hand and shadow and stuff and we green-screened Hugo in later! He wasn't originally in that scene but he is now."

And Gibson insists his interest in Hugo paid off, because the actor was amazing: "I think it's the best work any of the actors in this have ever done and I was really proud and pleased to be able to stand back and watch it happen.

"They had to tread some fine lines here, because they weren't necessarily doing things to make you like them. I just applaud all of them for making me look good (as a director)."