People aren't convinced by Cillian Murphy's accent in Christopher Nolan's Oppenheimer

People are pretty divided over Cillian Murphy's American accent in the latest trailer for upcoming film Oppenheimer.

The movie is about the life of scientist J. Robert Oppenheimer (Murphy), one of the major figures behind the development of the atomic bomb.

Given the star-studded cast and production values going into Oppenheimer there's already plenty of hype surrounding the movie, which is being directed by Christopher Nolan.

A movie focusing on the life of a major historical figure with such a big name director and stars attached to the project is making many think Oppenheimer will be a must-see when it ends up on the big screen next year.

The movie is set to release on 21 July next year, the exact same date as Barbie, so audiences will obviously have a tough decision to make when deciding which one to see first.

However, one thing people are picking out of the latest trailer for Oppenheimer is Murphy's American accent, with many viewers finding it 'so jarring' to hear him speak like that.

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People took to social media to say it was 'so weird' and 'unnerving to say the least' to hear the Peaky Blinders star speaking with a different accent.

However, while plenty found it a bit strange to hear the accent, they were also incredibly impressed at just how good it was, praising the actor for getting it 'spot on' even if they were so used to him sounding different.

A few said they were hoping someone would 'let Cillian Murphy be Irish in one of these movies' so he could finally use his real accent one of these days.

This isn't the first time we've heard Murphy using an American accent, but the one he deploys in Oppenheimer is so radically different to the way he's sounded before that it's messing with some people's heads.

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The director has heavily praised Murphy in the past, calling him 'one of the great actors, not just of his generation, but of all time'.

Nolan revealed that he had been waiting for exactly the right sort of project where he could direct a movie with Murphy in the leading role.

The pair have worked together plenty of times before, with the star appearing in supporting roles in Inception, Dunkirk and playing Batman villain Scarecrow in the director's Dark Knight Trilogy.

This will be the first of their collaborations where he will be taking on the leading role, with the director saying he felt he could 'put the most enormous weight - cinematic weight - on his shoulders' and the actor would be able to 'carry that burden'.

Nolan also recreated the first ever nuclear bomb detonation in history with practical effects, as he has often tried to avoid leaning too heavily on CGI during his career.