Join 'Mad Men's' Vincent Kartheiser on an Antarctic Honeymoon in 'Red Knot’ (Exclusive Video)

The indie film, also starring Olivia Thirlby, was improvised aboard a 350-foot ship

It was a once-in-lifetime invitation: Join a 23-day journey from Argentina to Antarctica aboard a steel research vessel, alongside 30 notable artists, writers and scientists, including actress Juliette Binoche, author Cormac McCarthy and whale biologist Roger Payne.

Photographer Scott Cohen knew he would be crazy not to jump at the opportunity, but he wasn’t so sure he necessarily wanted to take photographs on this trip.

“The day after the invitation,” Cohen tells The Hollywood Reporter, “I start thinking this would be a phenomenal set piece for a film, almost like shooting a road movie, but you're at sea. It also fit really well with a story I'd been taking notes on for a number of years, but had not yet written a script for.”

Cohen called back his friend and fellow photographer Gregory Colbert, who had chartered the ship for a project of his own, and asked if he’d be open to Cohen shooting a narrative film on the expedition. The ship would serve as the production’s transportation, lodging, canteen and set, while its crew and fellow guests would be the film’s extras.

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Colbert gave his blessing and told Cohen he could accommodate a cast and crew of 17.

“The daunting part of the idea was the ship was leaving in two months,” explains Cohen. “I would have to come up with a narrative that could be executed in an improvisational way because I wasn't going to have a polished script that had been through rewrites.”

Cohen quickly found actors who could handle the film’s improvisational nature and would embrace the unpredictable journey. He cast Vincent Kartheiser (Mad Men’s Pete Campbell) and Olivia Thirlby (Being Flynn and Juno) as a newlywed couple whose relationship is tested by an exploration into the vastness of the natural world.

“The 80-page outline I shot with was essentially guideposts for a new marriage,” explains Cohen. “It starts in the buoyant stage of what it's like when you first get married and then what happens when things become very real and you don't have the skills to communicate as a couple yet.”

Cohen knew he wanted to set the relationship against an expansive landscape, the problem being he couldn’t scout his locations ahead of time and didn’t know what natural wonder or landscape they would encounter next. The cast and crew would have to be nimble and adjust to situations on the fly.

For example, in this exclusive clip, Cohen tells THR they were filming an impromptu concert being performed by composer Garth Stevenson on the ship’s deck when everyone started spotting nearby whales.

Red Knot is playing at the IFC Center in New York.