Scott Cooper thinks Christian Bale is the "finest actor working today".
The 47-year-old filmmaker helmed the new Western 'Hostiles' which starred the former Batman star and Rosamund Pike, and Cooper admitted he wrote the film with his close friend in mind.
In an interview with Deadline, Cooper said: "Christian is my closest pal and we spend a lot of time together when we aren't working.
"I think Christian is the finest actor working today. He embodies characters in a way that is bone deep.
"So often, the type of performances that people think are award worthy, it falls under the idea that the most acting equals the best acting.
"I subscribe to the opposite. Christian is able to do something very few actors can; he psychologically embodies the character and the traits in a way that it takes what you've written on the page to a whole different, unexpected place. When you can do that with your closest friend, why not? I wrote 'Out of the Furnace' for Christian, and certainly wrote this with Christian in mind.
"He and I have very similar sensibilities; we become obsessed. Christian is not afraid to make unflinching or uncompromising movies, which we certainly did with 'Out of the Furnace' and now with this. I couldn't ask for a better partner because Christian understands character, story and tone so well. When I'm casting. He and I speak about every part in the film. We talk about the cinematic grammar of the story, all the things that a lot of actors don't want to concern themselves with. Christian does it because he's interested and curious and like me, obsessed. My wife often says, are you going to work with anyone but Christian?"
'Hostiles' follows Army Captain Joseph Blocker who reluctantly agrees to escort a dying Cheyenne war chief and his family back to their tribal land.
They soon encounter a young widow whose family was murdered and the travellers must band together to survive a dangerous landscape.