Documentary a son's personal memoir of famous father

When Louis I. Kahn died in a men's room in New York's Penn Station in 1974, he was considered by many to be the most important architect of the late 20th century. And yet at the time of his death, he was bankrupt, alone and so disconnected from the world over which he had sought mastery that his body lay unclaimed in a morgue for three days.

With the Oscar-nominated documentary "My Architect," Kahn's illegitimate son Nathaniel now has laid claim to Lou Kahn and the legacy of secrets and lies that upended his personal life.

Though the film's title is a bit baffling, its possessive "My" underscores the intensely personal nature of the documentary as memoir. As he uncoils the chaos that surrounded his father's life, you can feel the pleasure Nathaniel Kahn takes in finally having some control over his own story. And over his wayward father, who had a wife and two mistresses (one of them Nathaniel's mother) when his life ended abruptly at 72.

"He never married my mother, and he never lived with us," Nathaniel says at the outset of his narration, never modulating his voice for dramatic effect but still letting us in on his pain. Most of Lou Kahn's colleagues attest that they didn't even know he was married, let alone that he had "three families all at once," as Nathaniel puts it.

Nathaniel interviews his mother, whose weathered face and sad eyes say more about the terrible price she paid for loving Lou than she herself is willing to. He also talks to the woman with whom Kahn was conducting another long-running affair when he died. Then he has a sort of encounter session with Kahn's two daughters: one the offspring of his marriage, the other, like Nathaniel, illegitimate - a term that brought with it the wallop of judgment 30 years ago.

Their father's face bore the lifelong scars of a childhood fire, scars he seems to have passed on to those he left behind. Nathaniel's mother, who worked with Kahn on many of his designs but was forced to hide in an office supply room when his wife showed up, still believes he was coming to live with them when he collapsed. She never married and lives alone on the coast of Maine, still waiting.

Kahn was living proof that we indulge genius everything and ask questions later. Perhaps the force of his talent would have justified anything that he did to the few for the good of the many. Philip Johnson and I.M. Pei, the great owl-eyed fountainheads of modern architecture, make themselves sound like commission-whores compared to Kahn, whom they viewed as an artist.

"Three or four masterpieces is more important than 50 or 60 buildings," Pei says.

These assertions about Kahn's artistic legacy have the ring of truth, but they also highlight one of the undeniable pitfalls of this form of documentary memoir: Who would want to speak ill of the dead to Louis Kahn's son? When Pei describes Kahn's parallelograms of brick and light - the Salk Institute in La Jolla, the National Assembly Building of Bangladesh - as designs that will "stand the test of time," it's impossible to know if he's speaking forthrightly or merely attempting to be supportive.

Less ambiguous is the judgment of an architect Nathaniel encounters while visiting the Bangladesh parliament building in Dhaka. "He was Moses for us," says the man, welling up. "He gave us democracy."

"My Architect" assesses the geometric precision of the structures Kahn built and the moral ambiguities of the ones he tore down. Then it sets us free to decide who he really was.