Woody Allen is notoriously tight-lipped about his personal life, particularly his nearly two-decade-long marriage to Soon-Yi Previn.

But he broke with tradition and opened up about it in a lengthy interview with NPR, just a few weeks shy of his 80th birthday.

Some background: In 1992, Mia Farrow left Allen after 10 years together when she discovered nude photos that he had taken of her adopted daughter, Soon-Yi (her father is Andre Previn, Farrow's ex-husband). Allen and Previn married in 1997, when he was 62 and she was 27.

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"I started the relationship with [Soon-Yi] and I thought it would just be a fling, it wouldn't be serious," Allen told NPR. "But it had a life of its own."

"I'm 35 years older, and somehow, through no fault of mine or hers, the dynamic worked," Allen explained. "I was paternal. She responded to someone paternal. I liked her youth and energy. She deferred to me, and I was happy to give her an enormous amount of decision-making just as a gift and let her take charge of so many things. She flourished. It was just a good-luck thing."

"The age difference didn't seem to matter. It seemed to work in our favor, actually," Allen said. "She enjoyed being introduced to many, many things that I knew from experience, and I enjoyed showing her those things."

Allen also revealed his biggest regret (not finishing college) and whether he's ever done drugs (never — not even a puff on a joint). Read the whole thing here.

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