Josh O'Connor reveals the reason why fans should stick with slow burn of new film The Mastermind

Josh O'Connor is a man on the run in Kelly Reichardt's highly-anticipated The Mastermind.

In a quiet Massachusetts suburb, unemployed family man and amateur art thief JB Mooney sets out on his first art heist, and while he assumes it'll be easy to pull off, he soon finds himself a wanted man, leaving his wife (Alana Haim) and children behind.

The almost two-hour movie flips the script on the conventions of a classic heist movie, forcing audiences to pay close attention to the folly of man intertwined with the backdrop of art and crime.

Having done the festival circuit, the response to the movie has been divisive, with some early audiences gripped by the slow-moving Mooney as he evades the police and others disappointed at the movie's pace.

For those less familiar with Reichardt's work, O'Connor understands why The Mastermind may not immediately grip you – but there is much more to the movie than an art heist gone wrong.

Speaking exclusively to RadioTimes.com, O'Connor praised Reichardt as "one of the best celebrated filmmakers in the States", noting that "time after time [she has] made these extraordinary films that are often meditative and have a sensitivity to them".

He continued: "You've got to prepare to sit with a character and let them carry out their business in real time. She's not massively interested in cuts."

While The Mastermind is described as a heist movie, it isn't in a similar vein to the likes of the Ocean's movies or Now You See Me, with less flashy takes and a focus on the quiet yet arrogant disposition of the mastermind pinned against the backdrop of the growing tensions in the '70s in response to the Vietnam War.

"Personally that's why I wanted to work with her [Reichardt]," O'Connor added. "I'm a big fan of her movies and this is, I think, no different. There's sequences in this movie where if you weren't a fan of Kelly's work, you might be like, 'Come on', but it's one of those movies that I think people will really enjoy."

Particularly, O'Connor has the belief audiences will enjoy "being the fly on the wall and watching this man unravel in a sort of mundane, quiet way, which we are not used to, but perhaps it's closer to reality".

As much as O'Connor was keen on working with Reichardt, she was equally interested in him as her Mooney, after seeing his performances in God's Own Country and The Crown.

Upon receiving the script, O'Connor was enthusiastic about the story and the character of JB, "a man smart enough to get into trouble, but not smart enough to get out of it".

While getting into character, O'Connor had a mantra he would repeat before every scene, that Mooney's plan was a good one, despite it's many flaws.

O'Connor told RadioTimes.com: "He [Mooney] continually thinks it's going to work out. Before every scene I'd say to anyone who'd listen, like crew members or the director or the other actor, I'd be like, 'Guys, this is a great idea. You'll see, you'll see.

"So I think, for me, I had to believe that the whole way through, that the next thing is gonna work out."

The Mastermind is in cinemas now.

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