Oprah Says Her Biggest Failure Is ...

In a preview clip from the highly anticipated Piers Morgan interview with Oprah Winfrey, the queen of talk reveals what she considers the biggest failure of her career: when the movie "Beloved" bombed at the box office, where its opening weekend lost to "Bride of Chucky."

Oprah talks about the disappointment sending her into a tailspin, which drove her to eat thirty pounds of mac and cheese prepared by her personal chef, Art Smith. She admits to recognizing it as the "only time in my life I was ever depressed," adding that she remembered thinking, "If I don't come out of this, I am going to have to get some help."

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Morgan asked Winfrey what she learned from this rare failure among her great achievements, to which she replied, "I think you can experience [failure] infrequently if you get the lesson."

Watch the full interview when "Piers Morgan Tonight" premieres on Monday, January 17 at 9 PM ET on CNN.