In a new interview, the 64-year-old actor recalls that his co-star would hit himself and force himself to puke at times in order to summon the unhinged ferocity his character required in the new horror film.
"He's not interested in craft, I think," Dafoe tells MR PORTER. "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," he adds. "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."
In the film, Dafoe and Pattinson play Thomas Wake and Ephraim Winslow, a pair of men charged with manning a lighthouse. During their time together, isolation and madness take hold.
"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," Pattinson recalls to the publication of his acting method. "He didn't know I was doing it until one scene where I was absolutely forced to do it in close proximity."
Dafoe also revealed that Pattinson didn't like to rehearse, which broke heavily from how he prepares for roles.
"Rob Pattinson worked very differently from me," Dafoe states. "But I made no judgment 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."
While promoting the film at the Toronto International Film Festival in September, Pattinson spoke with ET about his imposing mustache in the film, admitting that he needed some movie magic in order to maintain the rugged look.
"The only thing about the 'stache is I had to keep dying it all the time because my mustache is very blonde, so it kinda looks like…like I'm a 12-year-old with a hormone problem," he explained with a laugh.
The leading man also chatted about the extreme conditions of the production, which included lots and lots of water and filming on location in Nova Scotia. However, he shared that he appreciated the extreme elements he faced while filming because they helped him immerse himself in the story.
"The conditions are nice though," he told reporters. "It's nice when something feels real."