There might not be a more difficult movie to make than a biography of an artist. Not only does the filmmaker in question have to try to capture the essence of a well-known figure but also the essence of his work.

Happily, "Pollock" comes as close as any film in recent memory to accomplishing both those feats.

That's not to say it's perfect, but at least it does give us some sort of insight into the late Jackson Pollock, this country's first "art star."

That the film should be so watchable shouldn't come as a huge surprise, considering the star is underappreciated character-actor Ed Harris, whose work as Pollock has garnered him an Academy Award nomination, and who has made a career of giving terrific performances, even with spotty material.

But what is surprising, is how well Harris does as a filmmaker — especially with such a tricky project; especially considering this is his directorial debut.

Of course, it might be a bigger surprise if the film was a dog, considering the cast Harris has recruited — including the similarly unsung Marcia Gay Harden, who is also the recipient of an Oscar nod.

But the smartest move here comes from screenwriters Barbara Turner and Susan J. Emshwiller, who based their screenplay on the biography "Jackson Pollock: An American Saga."

Rather than trying to cover Pollock's entire life in a little more than two hours, the screenplay concentrates on a condensed time period, beginning with his "discovery" in the early 1940s and climaxing with his self-destructive end in 1956.

Among the film's suppositions is that Pollock might have toiled away in obscurity had it not been for fellow New York artist Lee Krasner (Harden), his eventual wife, who nurtured and encouraged him, sometimes at the cost of her own career as an artist.

She served as a calming influence amid his fits of rage, and her patience and devotion enabled him to experiment with his subconscious-directed painting style, which, in turn, gave rise to the "abstract expressionist" movement.

Because of that innovation, he eventually became a huge success, gaining the patronage of art aficionado Peggy Guggenheim (played by Amy Madigan, Harris' real-life wife), and even garnering a huge write-up in Life magazine.

But that measure of love and success weren't enough for Pollock, whose drinking became more problematic, and whose search for understanding led him to a relationship that may have been his downfall.

In addition to having a well-crafted script, Harris has also surrounded himself with a first-rate crew, including award-winning cinematographer Lisa Rinzler and musician Jeff Beal, whose subtle score never intrudes.

What makes "Pollock" resonate the most, however, are the performances.

Harris makes the complex character surprisingly sympathetic and understandable, while Harden is a model of composure as Krasner.

(Actually, it seems a tad insulting that she only got a supporting-actress nomination, considering the size of her part in the film.)

"Pollock" is rated R for frequent strong profanity, violence (explosive temper tantrums), use of crude sexual slang terms, glimpses of nude artwork and brief drug use (amphetamines). Running time: 123 minutes.