The indefatigable Bill Cunningham has been prowling the streets for stylish types since World War II, child, when his camera of choice was a Brownie. Come September 3, the 85-year-old aesthete will pedal up to the 92nd Street Y—not to snap photos but to join Fern Mallis on stage for a rare interview. The event, announced today, will kick off the fourth year of Mallis’s “Fashion Icons” series, during which she has interviewed everyone from André Leon Talley and Bruce Weber to Tom Ford and Vera Wang with a surgical, this-is-your-life approach that inevitably reveals all manner of fun facts (did you know that Penelope Tree was a college classmate of Wang’s? Or that she herself had seven wedding dresses, in a nod to Chinese tradition?). Those interested in getting a peek at the man behind the blue French work jacket should grab tickets here, and fast. They’re likely to be gone in a flash.