Charlie Hunnam and Robert Pattinson’s latest role was an adventure in more ways than one. The two star together in The Lost City of Z, the true story of explorer Percy Fawcett, and each lost about 35 pounds for the role.

“I don’t think I was too much fun to be around,” Hunnam joked on Tuesday morning's Good Morning America. “The main conversation between us was, ‘Did you eat a second egg this morning?’ And sort of suspicious glances over,” Pattinson joked.

“Whenever anyone went off of set, you’d think, is he going to eat something?”

Credit: Todd Williamson/Getty for Amazon Studios

And that wasn’t the only sacrifice they made: In order to immerse themselves in their parts, they went totally off the grid while filming in Colombia. “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 said of his character. “I’m lucky that I have a very understanding girlfriend who allows me to go off and do these weird whims.”

“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.”

Hopefully the sacrifice paid off. See for yourself when The Lost City of Z hits theaters on Friday, April 14.