Adam Driver's extreme weight loss for his role in 'Silence' made him deliver more powerful lines.
The 32-year-old actor - who portrays a 17th century Jesuit priest alongside Andrew Garfield in the Martin Scorsese drama - was so undernourished after losing more than 30 pounds that it made his scenes more realistic.
He explained: "You're so hungry and so tired at some points that there's nothing you can do - you're not adding anything on top of what you're doing. You only have enough energy to convey what you're doing, so it's great."
Adam and his co-star Andrew Garfield, 33, had to continue to lose weight throughout the movie, which sees them travel for two years from Portugal to Macau and then onto Japan where they meet their mentor played by Liam Neeson.
However, it was sometimes hard to find the "energy" to deliver on set.
Adam told Interview magazine: "There are other times where a scene's not working and you don't have the energy to figure out why it's not working."
He added: "When the movie begins, the characters have been traveling for two years, from Portugal to Macau, sailed around Africa. There's disease and shortage of food. "They're already kind of depleted when they get to Macau before their last leg to Japan. There's a lot of storytelling happening off camera.
"He ( Martin Scorsese) wanted to see that physically. He asked us to lose a lot of weight. I didn't know how much that was going to be."
Despite suffering from sleep deprivation and extreme hunger, Adam found the whole experience fascinating.
He said: "I can't control what's happening in scenes, but I could control when I ate food.
"And that visual part of the storytelling, I don't think I've ever taken it to the extreme before. It's an interesting thing."
'Silence' hits screens in the US on December 23 and will be released worldwide in January.
Tagged in Liam Neeson