Katy Perry learned that the hard way when, during a scheduled sit-down with the veteran journalist, she happened be running behind schedule ... only to run straight into Walters's ire when the interview finally got under way.
In the latest issue of Billboard, the "Roar" singer, 28, looks back on the encounter, which happened to coincide with the demise of Perry's marriage to her then husband, Russell Brand.
"I shouldn't have done the interview: I was playing Madison Square Garden that same night, and I knew that the end of my marriage was coming. I was just exhausted and stressed," she tells the mag.
(Although Perry doesn't specify which interview it was, she did appear on Walters's "Top 10 Most Fascinating People of 2011" in December of 2011, just two weeks before Brand filed for divorce.)
Courtesy of Billboard
"When I got there, I apologized immediately, but then she said to me, 'You know, I've only ever waited for one other person this long, and you know who that person was? Judy Garland. You know how she turned out, right?' " Perry recalls.
"I was like, 'Oh, snap! Yes, b––!' " she says. "I think it's the coolest thing that Barbara Walters shaded me."
Still, Perry says it was a difficult moment in her pop music career.
"I just couldn't tell her as we were sitting down for a mega-interview, 'Hey, my marriage is falling apart. Give me a break.' "