Adewale Akinnuoye-Agbaje has revealed that his Thor role took its toll on him.
The British actor admitted he had to spend hours in the make-up chair to prepare for his portrayal of baddie Algrim and his alter-ego Kurse in Thor: The Dark World.
"It was very challenging but it was rewarding. It took three hours to get into Algrim, two hours to get into Kurse and on some days, I was playing them both at the same time so that took five hours into make-up," he said.
The 46-year-old continued: " You see Kurse trudging through (the film). It wasn't just because I was a great actor, it was because I had 40 pounds on my back. The weight kind of helped with the character, but ultimately when you see it in the movie, it was worth it."
Adewale spent time with co-star Christopher Eccleston, who plays his leader Malekith the Accursed, to develop their elvish language and to build on their bond.
"We spent hours outside of work just honing the language, the tone and even our movements. We wanted to be in sync and really give the audience something that they would fear and something that would resonate," he said.
"We didn't just want to do the quintessential baddies. We wanted a bond between us and it to transcend on screen, no matter whether we were wearing prosthetics or not. We wanted the heart of those characters to come out."
Thor: The Dark World, which also stars Chris Hemsworth, Natalie Portman and Tom Hiddleston, is in cinemas now.