James Franco has revealed he ended up with a purple arm after director Danny Boyle pushed him to the limits for new film 127 Hours.
The Spider-Man actor stars in the true story of mountain climber Aron Ralston, who hacked off his own arm with a penknife after it became trapped under a rock, leaving him stranded in a Utah canyon for five days with little food and water.
James revealed Danny pushed him to the limits during filming, making him experience as close as possible to the reality of what Arun had endured, and left him in pain after filming a scene struggling to pull his arm out from under a large boulder for over 20 minutes.
He said: "Danny does like to push his actors. He said to me 'So try and pull your arm out. Do anything that you can. Bash yourself against the rock, knee it, kick it, yank, pull, anything you can, and don't stop 'til I say cut.'
"And I said 'I'll probably be really bruised and exhausted and I'll probably get hurt.'
"And I said, 'Alright, I'm up for it but just make sure you get it on the first take.'
"So we did it and when he said 'cut' it had been 22 minutes and I was completely exhausted and the next day my arm was purple."
127 Hours, based on Aron's book Between A Rock And A Hard Place, is the closing gala premiere the BFI London Film Festival on Thursday.