'All Is Lost' Director J.C. Chandor on Robert Redford's Waterlogged Time at Sea (Video)

"We were joking the other day that we've kind of blocked out some of the elements, in a post-traumatic stress way," says the director of working on the drama with star Redford.

J.C. Chandor made an incredibly brave move for only his second feature film. He made a movie with just one actor (Robert Redford), no dialogue and set it on the water, which most filmmakers would tell you never to do.

Chandor, who previously helmed Margin Call, says there were very few actors who would have been right for the role of the lone sailor whose sailboat, the Virginia Jean (named after Chandor's two grandmothers), suffers an accident that leaves him stranded at sea.

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"I really zeroed in on the fact that I wanted it to be an older guy," he tells The Hollywood Reporter. "There's something sort of transcendent about that within the story -- his refusal to give up. Once we zeroed in on wanting it to still be this adventure film in a way, but also have this existential element, and have it be an older actor, the list gets short pretty quickly."

Chandor met Redford at the Sundance Film Festival before his first film, Margin Call, had even debuted. (The 2011 drama went on to be nominated for an Academy Award for best original screenplay.)

"He had said yes before Margin Call had even come out in theaters. I was literally just another filmmaker," says Chandor of Redford.

The film, which screened out of competition at the Cannes Film Festival in May, puts Redford's character through a variety of stressful situations, from the initial accident to a storm and a sinking boat.

Redford, who did many of his own stunts, spent a great deal of time being dunked in and out of water, or climbing around a tumbling boat.

VIDEO: 'All Is Lost' Trailer: Robert Redford Adrift at Sea

"It's kind of a miserable concept because you're taking off all these wet clothes knowing you're going to put on another set that's going to be wet again," says Chandor. "Toward the end, he started to not change into dry clothes, and would sort of stay wet."

Chandor also says that for some scenes, instead of dunking Redford in the water, the costume department would just spray him with a pressurized sprayer. "Toward the end I would literally have to look away because I felt so bad," says Chandor.

But all that time in the water and on the sea may pay off for Chandor and Redford, whose name has already been circling in awards conversations. The film opens in limited release on Oct. 18.

"We were joking the other day that we've kind of blocked out some of the elements, in a post-traumatic stress way," says Chandor with a laugh.

Watch THR's interview with Chandor above to learn more about the making of All Is Lost.

E-mail: Rebecca.Ford@THR.com
Twitter: @Beccamford