Robert Downey Jr. praises Cillian Murphy for making huge 'sacrifices' for Oppenheimer role

The weekend following two of the biggest film releases of the year is almost over, with millions heading to the cinema to watch Barbie and Oppenheimer.

Thankfully for us films geeks, the two polar-opposite flicks reviewed extremely well, with both set to be in conversation for movie of the year come December.

Oppenheimer, in particular, has particularly impressed with a 96 percent Rotten Tomatoes score on debut.

The Christopher Nolan directed movie tells the story of of American scientist J. Robert Oppenheimer (played by Cillian Murphy) and his role in developing the atomic bomb which was used in World War II - something he earned the title as the ‘father of the atomic bomb’ for.

With a run time of a staggering three hours, the film also stars Emily Blunt, Robert Downey Jr., Florence Pugh and Matt Damon.

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While the whole cast of the instant hit were praised, it is Murphy's transformative performance that has been particularly applauded by fans.

"I can’t even find the words to describe how good Cillian Murphy is, I just can't," one fan wrote on Twitter.

While a second added: "I’ve never seen any Cillian Murphy movie [before Oppenheimer], but I can tell he is about to become one of my favourite actors."

And these comments are certainly not few and far between, as many fans continue to flock to social media to commend the actor.

Now, Murphy's co-stars, Downey Jr. and Pugh, have praised the Peaky Blinders star.

Downey Jr. said he was impressed by Murphy's 'commitment' to the role, telling People: "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 Chris called him. But I think he also had the humility that is required to survive playing a role like this.

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"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."

Pugh, who spent a lot of time on-screen with Murphy, added: "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."

She continued: "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.