Willem Dafoe on 'The Lighthouse,' working with Robert Pattinson

Willem Dafoe torments Robert Pattinson in the new film, "The Lighthouse." The two met for the very first time on the set of the psychological horror-thriller and jumped right into character. Dafoe stopped by the ABC News studio to promote the film and talked about meeting Pattinson.

"I didn't know him and I didn't know him during the shoot because it was so intense," Dafoe said in an appearance on "Popcorn with Peter Travers." "And we were shooting in very difficult circumstances because a lot of it's outdoors and we were on this rocky peninsula where we built this lighthouse. And the weather was really extreme, really strong, so basically I just knew him within the scenes."

He added, "it was only afterwards when we started doing press that we hung out a little bit and I got to know him."

Dafoe and Pattinson play lighthouse keepers, the movie's only two characters, who unintentionally become isolated on an island off the coast of New England. The two try desperately to maintain their sanity while trapped on the island.

"The character I play, he's an unreliable narrator," Dafoe, 64, told Travers. "You're not sure when he's telling the truth and when he isn't. There's a lot of mystery in this."

Download the all new "Popcorn With Peter Travers" podcasts on Apple Podcasts, Spotify, Tunein, Google Play Music and Stitcher.

"The Lighthouse" is in theaters everywhere.

Be sure to watch the full interview with Peter Travers and Willem Dafoe in the video above.