A voyage into the unknown: Casey Affleck on his role in The Finest Hours

The actor talks about making the switch from his usual low-key indie-movie roles to a CGI-packed blockbuster, how he handles fame and what he's up to next.

Casey Affleck as Ray Sybert and Josh Stewart as Tchuda Southerland struggle to keep their ship, the SS Pendleton, from sinking in The Finest Hours. Claire Folger / courtesy Disney

James Mottram

"It was…not like anything else I've ever done," says Casey Affleck, pausing for dramatic effect. He's talking about his role in The Finest Hours, the new Disney-backed blockbuster set on the high seas.

Affleck normally leaves the bigger, ­blockbuster-style movies to older brother Ben – who will soon be seen suited up as the Dark Knight in Batman v Superman: Dawn of Justice.

Casey, 40, is usually more at home in the indie arena, in films such as The Killer Inside Me and Out of the Furnace.

Not so in The Finest Hours, which evokes the spirit of classic sea-based thrillers such as The Perfect Storm and The Poseidon ­Adventure.

Directed by Craig Gillespie (Million Dollar Arm), it tells the little-known true story of a small team of coastguards who went above and beyond the call of duty one winter's night in 1952 in an attempt to rescue the crew of an oil tanker, the SS Pendleton, which split in two off Cape Cod during a massive storm.

While the rescue team is led by Chris Pine’s hard-working hero Bernie Webber, Affleck plays Ray Sybert, the stricken vessel’s chief engineer, who takes command of the survivors when the accident happens.

Affleck was surprised at just what shooting a big effect-driven movie like this entailed.

“I’m making a generalisation, but there was very little scene-work,” he says. “It was a lot of standing on a fake ship rocking back and forth in a warehouse, with a rain machine and a wind machine and a big blue screen behind you.

“It required a lot of imagination on the one hand, and on the other hand you’re just getting pelted with rain and you have a big fan in your face.”

Affleck chuckles at how ridiculous it sounds.

“You just stand there and blink,” he says. “You just respond to the elements – and whether they’re artificial or not, they’re elements nonetheless – and you look into thin air when a wave crashes into you. Then they yell ‘cut’!

“It was a lot of fun – though some poor guys got hypothermia. But I guess it’s probably easier than being a coastguard.”

For Affleck, one of the few actors in the film sporting an authentic New England accent, the shoot took him back to Boston, where he’s from.

"I got to be home for a while," he says, and it is evidently something that means a great deal to him. He filmed Good Will Hunting (starring his brother) and Gone Baby Gone (directed by his brother) in the area, and returned for Kenneth Lonergan's Manchester By The Sea, one of this year's most buzzed-about movies at last month's Sundance Film Festival.

What The Finest Hours didn't manage was to pair Affleck up on screen with his friend and co-star Ben Foster. This is their second film together, after rural drama Ain't Them Bodies Saints, but they have yet to appear together in a scene.

“I never get to work with him,” says Affleck. “I’ve done two movies with him and I’ve never been on camera with him.

“I really admire him. He’s got something special as an actor.”

The same could be said of Affleck, an actor who prefers having his privacy to movie-star exposure. Although he's been on screen for more than 20 years, since his debut in Gus Van Sant's To Die For, he admits there are still difficulties in handling fame.

“For the most part, it’s not easy,” he says. “I think everybody wants to keep the opportunities that fame affords you – the money and the opportunity to work on different movies. But I don’t know … there aren’t so many people who like the rest of it. I certainly don’t.”

He will next be seen in Triple 9, a heist thriller co-starring Kate Winslet and Breaking Bad's Aaron Paul which is due for release this month in the United States.

And he is about to start work on Far Bright Star, his second film as director. Based on the novel by Robert Olmstead, it is survival tale set in 1916 against the backdrop of the Mexican Revolution, with a script that was adapted by screenwriter Damien Ober.

“It just came out really, really well,” he says. “It’s something I’ve wanted to make for a while.”

Set to star his real-life brother-in-law Joaquin Phoenix (Affleck has been married to Phooenix's younger sister Summer for almost a decade) it is likely to prove considerably less controversial than their last collaboration, the Affleck-directed mock-documentary I'm Still Here, in which Phoenix played a bizarre, messed-up version of himself. Is Affleck expecting big things from the film?

“I’ve never experienced anything but a modicum of success or total failure,” he says. “I don’t expect much else when I go do a movie.”

The Finest Hours is in cinemas now