Charlie Hunnam, Robert Pattinson Went Completely Off the Grid Filming 'The Lost City of Z'

Charlie Hunnam, Robert Pattinson Went Completely Off the Grid Filming 'The Lost City of Z'

Charlie Hunnam and Robert Pattinson took their roles in The Lost City of Z very seriously. So seriously, in fact, that they cut off communication with the outside world during filming.

"I felt as though it was going to require more from me than I'd ever had to give," Hunnam, 37, said in a joint interview with Pattinson for Good Morning America on Tuesday, April 11.

The movie, which is based on true events, stars the Sons of Anarchy alum as Percy Fawcett, a British-born explorer who went missing in 1925 while on an expedition to find a mythical ancient city in the Amazon. Pattinson, 30, plays one of his traveling companions.

"He would go on these grand, heroic explorations into the jungle for three or four years at a time and have no contact with his family at home," Hunnam explained of Fawcett.

With that in mind, the Queer as Folk actor decided to go completely off the grid. "I didn't use email once. I didn't go on the computer. I didn't make a phone call for four months. It was so liberating," he told GMA, noting that his girlfriend of more than a decade, Morgana McNelis, is "very understanding." (He previously told Entertainment Weekly he tried to keep in touch with McNelis via snail mail at first, but then decided to just stop writing, "which obviously makes me sound like a total bastard, appropriately so.")

Pattinson laid low too. "It's incredible. 'I'm sorry, I have to go for six months and I am deeply in character. Don’t call me,'" he joked, laughing.

Less incredible? Having to drop 35 pounds for the movie. "I don't think I was too much fun to be around," Hunnam admitted of his strict diet during the shoot.

"The main pivotal conversations were about saying, like, 'Did you eat a second egg this morning?'" Pattinson quipped.

"And sort of suspicious glances over," Hunnam added. "Whenever anyone went off of set, you'd think, 'Is he going to eat something?'"

Hunnam previously spoke about getting into character in an interview with ScreenDaily, saying he "wanted to be away from everybody" and even "avoided [people] in the lunch room." Pattinson took a similar approach — Hunnam said they didn't speak "more than 10 words" off camera.

"I didn't know if he was just 'in that zone' or if he genuinely didn't like me," he told ScreenDaily of the Twilight alum. "There was a real distance between us."

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