About 10 years ago, the playwright John Guare got a call asking if he wanted to meet David Bowie to discuss a theater project.

As Mr. Guare remembered it, Mr. Bowie was “in a very dark place” (it was shortly after he had had a heart attack onstage in Berlin), and a mutual friend, the English producer Robert Fox, was trying to coax him back to a creative life. Mr. Guare immediately said yes.

He and Mr. Bowie met at each other’s homes in New York to throw around ideas, and sometimes they went out. “We would take walks around the East Village,” Mr. Guare said. “And I was always praying somebody would run into us so I could say, ‘Do you know my friend David Bowie?’”

It never happened.

Mr. Guare was at first puzzled and then amazed at how Mr. Bowie — the stage creature, the persona, the guy he saw command an audience at Radio City Music Hall in 1973 with his spiky orange hair and snow-white tan — could walk the city streets unrecognized.