"Shadow Dancer," set against a backdrop of a Northen Ireland in transition, gave the festival a lift after it premiered earlier this week following some of the higher-profile U.S. fiction films that have failed to live up to pre-festival hype.

The film stars Andrea Riseborough as a Belfast mother who, along with two of her brothers, is active in the Irish Republican Army when she gets offered a deal by an British intelligence officer (Clive Owen) to turn against her colleagues and become an informant or else go to prison.

James Marsh, who made Oscar-winning documentary "Man On Wire," directed "Shadow Dancer" which 1990s Northern Ireland TV correspondent Tom Bradby adapted from his book of the same name. Marsh said he was initially reluctant to work on the movie but ultimately won over by the idea of telling a more personal story of the conflict.

"In Britain you have this sort of exhausted sense of the Northern Irish troubles," he told Reuters. "But I quickly got caught up in the premise of the story where you take a young single mother and you go and force her to spy on her own family. It's an impossible bargain."

The moral quandary of Riseborough's character -- choosing between loved ones and dealing with the guilt of betrayal -- are themes most audiences could relate to, said Marsh.

Marsh applauded other films such as 2002's "Bloody Sunday" that captured a particular episode of the Northern Ireland conflict, but said he was more interested in the microcosm of one family's turmoil and how it reflected the region's larger troubles.

"We didn't try and bring in the bigger political story or the facts involved in this conflict. It felt like a very boiled down family thriller," he said, adding he was not interested in getting "flashy and flamboyant."

His restrained style has been lavished with praise. The Hollywood Reporter hailed his "carefully crafted" film, while The Guardian called it "a poetic and unapologetically arthouse story of betrayal and loyalty that, with its terrific score, measured pacing and fierce female performances, is a raw reminder of a sad and painful past."

RISEBOROUGH ON THE RISE

Working alongside a support cast of Irish actors, the English-born Owen agreed only at the last minute to take the role, while American actress Gillian Anderson turns up in an unrecognizable role as Owen's frosty British boss.

In the main role is English-born Riseborough, 30, who was recently seen playing Wallis Simpson in Madonna's "W.E." Marsh said she was partly cast due to her turns as "a surprising actress, every role she did, you didn't quite recognize her."

"She has something of the quality of a silent movie actress, you can photograph her in close-up and so much is available so discreetly," he said.

Filmed over 5 weeks in Dublin and one week in London, the cinematography features strong shades of gray in stark contrast to Riseborough standing out in a rich red raincoat in tones that Marsh said were inspired by the 1964 Hitchcock film "Marnie."

Marsh, 48, was offered the film after directing "1980," the second movie of the "Red Riding" trilogy. "Shadow Dancer" is his largest fiction feature to date, but he said making fiction films -- as opposed to documentaries like "Man on Wire" or last year's "Project Nim" -- was always a part of his dream.

"The one thing you want from your career is one film leading to another film, and that hasn't always been the case for me. So I am just thrilled to be working and making films," he said. "I am as happy as can be."

"Shadow Boxer" is not the only foreign film winning fans at Sundance, which is considered the premiere festival for U.S. independent moviemakers but in recent years has lured more work from overseas and launched a world cinema competition.

"Wish You Were Here," the Australian drama starring Joel Edgerton as a father struggling to keep his family and himself together after a disastrous holiday, has earned praise. As has "The Raid," a bloody, bone-crunching, martial arts action drama from Indonesia that played at the Toronto film festival.

Also receiving a warm response has been "Madrid, 1987", Brazil's "Father's Chair," Chile's "Violeta Went to Heaven," and Turkish drama "Can," the first Turkish film to play Sundance.

(Reporting By Christine Kearney; Editing by Bob Tourtellotte)

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