Robert Downey Jr. heaps praise on Cillian Murphy for Oppenheimer role

Oppenheimer is without doubt going to go down as one of the biggest films of the year. It will probably go down as one of the biggest films of the decade. And going off the rave reviews from critics and viewers alike, it could go down in the movie history books.

The movie has been both a box office and a critical hit, taking in $82.5 million in its opening weekend and receiving 94% on Rotten Tomatoes, with some critics suggesting it's an early runner for the Best Picture Oscar.

As I'm sure you're all now aware, the film follows Cillian Murphy in the titular role, playing Robert Oppenheimer, the father of the atomic bomb that was later dropped on both Hiroshima and Nagasaki, Japan, bringing an end to World War II.

Robert Downey Jr., who plays Lewis Strauss, chairman of the Atomic Energy Commission, spoke to People about Murphy's performance.

The actor explained: "I have never witnessed a greater sacrifice by a lead actor in my career.

"He knew it was going to be a behemoth ask when (writer-director) Chris (Nolan) called him. But I think he also had the humility that is required to survive playing a role like this."

Downey referred to just one of the sacrifices Murphy had to make, remembering: "We'd be like, 'Hey, we got a three-day weekend. Maybe we'll go antiquing in Santa Fe. What are you going to do?' 'Oh, I have to learn 30,000 words of Dutch. Have a nice time'. But that's the nature of the ask."

Florence Pugh, who plays Oppenheimer's lover, Jean Tatlock, also spoke highly of Murphy's role, saying: "Chris had one of the most incredible leads in Cillian. He is an actor that I have been watching for quite some time and have been desperate to work with for ages.

"You’d have to be mad to say no. It was truly one of the best experiences that I’ve had. Working with him was hugely impressive.

"Every single day he shows up knowing every single possible way, intonation, inflection of how to bring this character to life. That was hugely impressive to me. There's a reason why he is one of the greats."

Oppenheimer is in cinemas now.