Bradley Cooper has described 'Maestro' as the "most terrifying" film of his career.
The 48-year-old star will portray the acclaimed conductor Leonard Bernstein in the biopic and is amazed by how difficult the profession is.
In a Focus Features roundtable with 'Tar' star Cate Blanchett and director Todd Field, Bradley said: "Having worked on a project in the same world (as 'Tar'), the level of respect that I have for that world and that podium, it is the most terrifying thing I've ever experienced.
"And it's so odd because so many people – I don't know if you've come across this – but people that I have met in the last five years have said, 'Well, what is it that conductors even do? Aren't you up there sort of doing like this?'"
Bradley – who is also directing the Bernstein biopic – added: "And my answer is, 'It's the absolute hardest thing you could ever want to do. It is impossible.'"
The 'A Star Is Born' actor had high praise for Blanchett and Field for making conducting look easy in 'Tar'.
He said: "Not only did you make the conducting look easy, but the rehearsal. The rhythm of the rehearsal and the way you wrote and filmed it was just so appetising on every level as a viewer. It was truly mind-blowing... There's no one else who could ever play that role (of Lydia Tar)."
Steven Spielberg and Martin Scorsese are both serving as producers on 'Maestro', which will be released this year on Netflix.
Spielberg had considered directing the flick but ultimately stepped aside to allow Bradley to continue his work behind the camera following his acclaimed directorial debut on the 2018 remake of 'A Star Is Born'.