“I’m sorry to interrupt, but could you guys please finish up?” a woman asked Nocturnalist’s correspondent at Town Hall theater on 43rd Street on Thursday night as he conducted an interview. He was sitting in her seat, she said.

Our interviewee turned and stared at the woman expressionless. “Oh my goodness!” she screamed. “I’m so sorry!” Bill Cosby does not do interruptions.

Mr. Cosby, who was to perform at a benefit for Art Start, which provides creative arts to at-risk children, many with parents in homeless shelters, also will brook no red-carpet churlishness. As he bypassed a gaggle of paparazzi to speak to us, a crestfallen photographer called after him. “Hey Bill! Come on, man!”

Mr. Cosby turned, and lunged. “Don’t you ever ...” he said, grabbing the photographer by the shirt. The next day’s sensational headlines flashed before our eyes. We readied our pen.

But Mr. Cosby smiled. It was just a joke. (The shaken photographer seemed to have a different sense of humor.)

“The reason why I’m here tonight, with great emotion, is because I was asked to perform,” Mr. Cosby said, once we sequestered ourselves in the theater’s seats. He added some thoughts about the importance of the foundation’s work, and also noted, “They are paying me.”

Johanna De Los Santos, the executive director of Art Start, later clarified that a supporter of the organization was paying him.

At the after party at Sardi’s, Mark Nadler, who had also performed at Town Hall along with the Broadway legend Chita Rivera, leapt onto a chair. “Excuse me, gentleman and sluts!” he shouted, before proclaiming that the event had raised $100,000. He hoisted his martini. “Nobody’s working tomorrow!”

An aerialist who had been arrested earlier this year for scaling the Williamsburg Bridge, Seanna Sharpe, was with a man in a Hamburgleresque cape. “According to my publicist, I can’t answer any questions until after I appear on Good Morning America,” she said before divulging some of the details of her case.

Stars of yesteryear abounded, like the cabaret singer Julie Wilson, whose friend showed us a photo on an iPhone of Ms. Wilson as a starlet. Ms. Wilson glanced at it. “Oh, that old bag. Is she still around?”

Celeste Holm, the 94-year-old Oscar-winning actress, and her husband, Frank Basile, 48, entered. “When she turned 90, Bill Cosby sent her 90 long stem roses,” Mr. Basile said of his wife. She leaned forward and whispered: “That’s true.”