When Barbara Walters interviews guests for her many TV specials, they generally have a comfy green room in which to prep beforehand. Not so when the tables were turned at Manhattan Criminal Court on Thursday — after walking the gauntlet of photographers and TV crews that set up camp in the court hallway, she was ushered into a stark, linoleum-floored witness room without even a water fountain.

Walters was at 100 Centre Street to take the stand against her friend Brooke Astor’s son, Anthony Marshall, in the criminal trial in which he’s accused of using undue influence to alter his mother’s estate to his benefit. There, the TV interviewer discovered getting grilled isn’t as much fun as doing the grilling. “It’s tough getting interviewed, isn’t it?” said one of the prosecutors.

This story first appeared in the May 22, 2009 issue of WWD. Subscribe Today.

“Yes, exactly,” responded Walters, clad in a vintage Bill Blass suit. “Well, the rules are a little different here,” offered one of the defense attorneys.

Indeed, not everything went as scripted: as Walters began her testimony, the cell phone belonging to Marshall’s wife, Charlene, began ringing loudly. Turning beet red, she dug through her bag to turn it off.

Meanwhile, Walters reminisced about Astor, who she met in the Sixties at a dinner party thrown by Newsweek editor Lally Weymouth. “I remember Mrs. Astor because she was the only guest wearing a hat — a hat with a veil,” she said. Back in those days, and even through her 90s, Astor was still walking three to five miles a day, swimming, drinking scotch in the evenings and dancing up a storm.

“I try to drop one old person a year and get one new young friend,” explained Astor of the secret to youth in a 1993 “Nightline” interview that Walters conducted.

The two pals lunched regularly at The Four Seasons. “I took her once to Swifty’s, but most of the patrons were women and she said, ‘I don’t want to come here again. There are no men,’” recalled Walters.

She also testified Astor wasn’t fond of her daughter-in-law (joined in the gallery Thursday morning by her daughter, Inness, Sam Peabody and in the afternoon by Broadway actor Jefferson Mays, whose play, “I Am My Own Wife,” Marshall produced). At her 100th birthday party at David Rockefeller’s estate, Charlene presented roses sent on behalf of Prince Charles. “And [Brooke] made a terrible face. She liked the flowers, but not being given to her in that way,” remembered Walters.

After that birthday party, in 2002, Walters said she noticed a decline in her friend’s health. On one visit, she brought a gold pill box as a gift for Astor. “At the end of the visit, she took out the pill box and said ‘I’d like to give this to you.’ I said, ‘Brooke, I gave that to you.’”

Her final visit was in December 2003, three-and-a-half years before Astor died. “She didn’t know me at all,” said a visibly sad Walters, saying Astor could barely speak. “I said, ‘Brooke, it’s Barbara.’ I just knew that she had no idea who I was.

“After that visit, I felt there was no purpose to my visiting,” she continued. “I wasn’t bringing her any pleasure and it was painful.”

Speaking afterward, Walters said, “She was so out of it [that day]; it was very distressing.” Walters herself also was mildly discomfited by the ordeal of being cross-examined. “It’s very different to sit in a courtroom,” she said. “You have to be more accurate — it’s very different from the way we work.…It’s been very edifying.”

Earlier in the day, 85-year-old Henry Kissinger testified and charmed everyone in sight, even planting a kiss on the cheek of the court officer who helped walk him in and out. “My heart is still pounding,” said the blushing guard. The former Secretary of State explained he and Astor had strict rules for their friendship, which began in the mid-Seventies: “On our walks, we couldn’t discuss substance, we could only discuss people,” he said. “Gossiping?” asked the prosecutor. “Yes,” he said. Their tight-knit circle included Walters, Bill Paley and Oscar and Annette de la Renta. With Paley, Kissinger and his wife Nancy even traveled to Malta, Egypt, Oman and Morocco. “It was a challenge” keeping up with Astor’s energy levels, he admitted.

As she approached her 100th birthday, he, too, noticed a change. At a dinner she threw in honor of her good friend Kofi Annan, Astor suddenly leaned over to Kissinger and asked, “Who is the black fellow who is sitting on the other side of me?” Kissinger told her, and she asked, “Is he a distinguished man?”

“Yes,” said Kissinger.

“She seemed to just not know who he was,” he said.

After that year, he and Nancy stopped visiting Astor, largely because she no longer seemed to recognize them either. “We were afraid it would be too much of a strain,” he said.