'Culture is the soul of a country," says Roland Eng, former Cambodian ambassador to the United States, in Dancing Across Borders. What happens when an artist is transplanted from his cultural tradition into another? Is the soul damaged in the process?

Dancing chronicles the giant leap of Sokvannara "Sy" Sar, a Cambodian folk dancer, from a community center in Angkor Wat to the stage of the School of American Ballet in Manhattan.

The nimble and charismatic performer equipped with a Slinky spine and trampoline feet did not initiate his passage to New York. Then 16, Sy was sponsored by Anne Bass, the philanthropist and balletomane, who directed this look at his evolution as a dancer.

While on camera, Sy (pronounced See), alternatingly impish and wistful, is candid about his homesickness and his mixed feelings toward America and ballet.

Yet the film is not forthcoming about Bass' motives for bringing him to the States and the nature of their relationship. Is Bass his patroness, his surrogate mother, his life partner? These unanswered questions linger over the film like a stubborn smog.

Though it's a joy to watch Sy move with unself-conscious exuberance, it is painful to see him struggle with the expectations thrust upon him.

Peter Boal, then of the School of American Ballet, examines Sy like livestock: "Good feet, good extension." Soon Olga Kostritsky, ballet teacher to Mikhail Baryshnikov, is in place as Sy's coach and head cheerleader, saying: "At first his body cried. His muscles weren't ready for ballet."

Most dancers begin training between the ages of 8 and 11; Sy was almost 17 when he began, telescoping 12 years of training into three years of "ballet boot camp" while also learning English and attending school.

It is hard to know to what extent Sy's struggles are universal to the world of competitive ballet and which are specific to his situation.

When he dances, the movie soars high as the sky. But when Sy talks about "trying to do the right thing," by which one assumes dancing to help out his family financially, the heart aches.

Sy is Dancing as fast as he can, but is it for himself - or others?

It becomes very hard during this uneven and unsatisfying documentary to know whether Bass made this bittersweet film to document Sy's struggle - or her own.

Dancing Across Borders **1/2 (out of four stars)

Directed by Anne Bass. Distributed by 123 Productions. In English and Khmer with English subtitles.

Running time: 1 hour, 28 mins.

Parent's guide: No MPAA rating (ballet documentary).

Showing at: Ritz at the Bourse.EndText

Contact movie critic Carrie Rickey at 215-854-5627 or crickey@phillynews.com. Read her blog, "Flickgrrl," at http://www.philly.com/philly/blogs/flickgrrl/.