Think of the late Bill Cunningham's charming memoir, "Fashion Climbing," as a prequel to the 2010 film "Bill Cunningham New York."

The documentary introduced people who don't read New York Times fashion coverage to the modest, bicycle-riding octogenarian who photographed Manhattan street fashion for several decades while living in a shoe-box apartment above Carnegie Hall. "Fashion Climbing" begins with him moving into a previous Carnegie apartment and details, with characteristic restraint, what he did in the years before the Times hired him.

Mostly, what he did was make hats. Obsessed by clothing from an early age, Cunningham filled a series of sketchbooks. He was diverted by a stint in the Army, where he covered his helmet "with a dazzling garden of flowers and grass," and where he hoped to check out Paris runways during his downtime, although he knew U.S. defense forces had shifted from Europe to Korea.

Anyway, hats were his calling, and, when he returned from his bedazzled service to Uncle Sam, Cunningham opened his own millinery studio.

In both the memoir and the film, Cunningham comes off as a screwball mix of sophisticate and naif. (Apparently written from the '40s to the '60s, the manuscript was only recently discovered.)

He seems to have dished more as a young man than as the elder version, since in the film he doesn't have a bad word to say about anyone. In the memoir, he calls out designers he thought were coasting (ahem, Christian Dior) and society matrons too sheeplike to recognize how fabulous they'd look in the enormous octopus hats he cranked out in his shabby atelier. (Bonkers even by today's standards, his hats must have seemed like alien invaders back in the conformist mid-1950s.)

Cunningham works in a few celeb cameos and gets off a couple of shots at duplicitous John Fairchild, who gave Cunningham his first writing gig, for Women's Wear Daily.

What Cunningham does not do is reveal himself. A childhood incident, when his mother discovers him wearing one of her dresses and beats the daylights out of him, is the only clue about what the memoirist felt deep inside. As in the documentary, Cunningham says little about his personal life, to the extent that it seems possible he simply didn't have one.

A few times in "Fashion Climbing," he mentions "girlfriends," but they seem to be more like "girl friends," and he lists one or two gay men in passing without hinting whether he felt a kinship. Even his devout Catholicism gets only a brief shout-out.

In his chatty preface, Hilton Als implies Cunningham was "queer" and always "couldn't believe his good fortune" but doesn't pause to wonder what Cunningham's unfailing cheerfulness may have cost him. It goes without saying that his delightful book doesn't address that, either.

Maybe the best we can hope for is that, somewhere in a trunk above Carnegie Hall, there's a second volume that will bring us up to date?

Chris Hewitt is a Star Tribune features writer and theater critic.

Fashion Climbing: A Memoir With Photographs
By: Bill Cunningham.
Publisher: Penguin, 240 pages, $27.