Robert Pattinson ''beat himself up so bad'' shooting 'The Lighthouse'.

The British actor surprised his co-star, Willem Dafoe with the ''wacky'' methods he adopted to get into character for the drama, including trying to make himself sick for a scene where both their characters were drunk.

Willem said: ''He's not interested in craft, I think. He wants to throw himself into deep water and he feels like it will only be true if he's drowning.

''Which, for this role, is perfect because that's the state he's going to be in. For me, that seemed wacky. But I'm not trying to judge.

''He has a good sense of the visual, of what's needed in a close-up. Sometimes he'd beat himself up so bad. He'd stick his fingers down his throat, things like that.''

Robert added: ''I would sneak off into a corner and gag, away from Willem. I think everyone feels very emotional when they're throwing up, and it's quite a nice little trick to get there. He didn't know I was doing it until one scene where I was absolutely forced to do it in close proximity.''

The two stars prepared for the movie ''very differently'', with the 33-year-old actor more reluctant to rehearse but he admitted he used their run-throughs to ''cheat'' and figure out how his older co-star would play the scene as he realised his own acting is more predictable.

Willem told Mr. Porter magazine: ''Rob Pattinson worked very differently from me. ''But I made no judgement on it because he had a different job. And also, I don't need him to work the way that I work. If I want to, I can work the way he works. He's a more reactive character. He's acted upon. So, it was very different.

''He doesn't like to rehearse. He prepares, but he prepares by himself.''

Robert confessed: ''I sort of used the rehearsal process [to try and] see all of Willem's cards, which frustrated him.

''It's quite competitive, the two parts, and so I guess I was trying to cheat as much as I could going up against someone like Willem.

''As soon as I could see that he knew what I was going to do, it would make me really sad. I was trying to surprise him as well as myself every time. He seems to be able to do a scene in an infinite number of ways. I feel like I've only got maybe five ways to do it.''