What was once upon a secret for decades — is a secret no more.
A former White House intern, after staying silent for decades, is now going public about her alleged affair with one of America's most popular presidents.
In her new tell-all book, "Once Upon a Secret: My Affair with President John F. Kennedy and Its Aftermath," Mimi Alford holds nothing back as she details their "sexual and fun" encounters.
In an interview with NBC's Meredith Vieira airing Wednesday evening on "Rock Center with Brian Williams," Alford calls Kennedy a "sensualist."
The ex-intern says the trysts began in the summer of 1962. She was 19. He was 45. She only addressed him as "Mr. President" — not by his first name.
Alford alleges the 18-month affair started on the fourth day of her new job, with a swim at lunch. "It really didn't seem unnatural just because everybody was friendly and I went back to work afterward."
"No one said anything."
After that swim, she says, the president invited her to tour the residence. She was led to Jackie Kennedy's private bedroom, where Alford lost her virginity to the president.
Alford says she doubts she could have thwarted his intentions and felt "overpowered" by the president. "I think overpowered in the sense that he was the president. He was this unbelievably handsome man, 45 years old — not overpowered physically that someone had grabbed me and made me do something that I wasn't really willing to do — because I really think I was willing to do it."
Alford says Kennedy enjoyed acting "completely silly," especially in the bathtub.
She says he "had a collection of little yellow rubber ducks and they were in the bathtub and rubber ducks sort of became part of the game."
But as close as the pair sounded, Alford admits there were boundaries. She writes, "...we never kissed."
"The wide gulf between us — the age, the power, the experience — guaranteed that our affair wouldn't evolve into anything more serious."
After decades of staying mum, Alford felt she had to speak out. "When you keep silent about something, you do it because you think it's keeping you safe."
She adds, "If I had said no, I think the president would have stopped."
Looking back, Alford says, "I should have felt guilty. He was married to Mrs. Kennedy, but I didn't at the time feel guilty."
But she adds, "I don't actually regret that I had the affair with President Kennedy... It was too much fun."
With files from NBC News; and Global National's Eric Sorensen
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