Woman reveals details of sex affair with JFK

>>> more on the former white house intern who claims she had an 18-month affair with president john f. kennedy . mimi alford details her experience in "once upon a secret." she sat down with meredith vieira for an exclusive interview for tonight's "rock center" with brian williams . good morning.

>> good morning to you. this is a story that mimi alford kept secret for 50 years. she didn't talk about it publically. she was outed in a historian's book in 1953 and admitted she was indeed the mimi who had the affair with jfk. then she basically disappeared until now.

>> most mornings when i woke up i thought, i don't want to get up and write this book. i want to hide under the covers.

>> what made you get out from under the covers?

>> i think when you keep a secret and keep silent about something you do it because you think it's keeping you safe, but in fact it's deadly.

>> reporter: the secret, claims alford , started in the summer of 1962 when the 19-year-old debutante from a prominent new jersey family began what she says was an 18-month affair with president john f. kennedy .

>> i was sort of swept into this web. the handsome president, his charisma, magnetism.

>> reporter: mimi said it began on the fourth day of her new job as a white house summer intern when she received a phone call from dave powers , the president's close aide.

>> he said, a group of us are going to have a swim at lunchtime. would you like to join us? i thought, well, it was a little bit odd to be swimming in the middle of the day at work. where's the pool? i didn't know the white house had a pool. of course i didn't have a bathing suit either. he said, don't worry, there are bathing suits .

>> reporter: in this heated pool, mimi found herself with two other young white house staffers.

>> they were in the water and dave escorted me in. shortly thereafter the president arrived. no one said the president was going to join us. he put on his trunks and came into the water.

>> reporter: hours later she was taken on a private tour of some of the rooms of the residence by her president where she lost her virginity to him in jackie kennedy 's private bedroom. did he realize if you were a virgin?

>> i think he did. he kept asking me if i was all right. i was all right. there was not a lot of conversation.

>> reporter: here you are a young woman . you have never had sexual relations before at 19.

>> no.

>> reporter: by your own account naive.

>> yep.

>> reporter: you have just had sex with the president of the united states . how can you be all right?

>> i didn't start to cry. i was hysterical. i clearly wanted to go home. and i did, very quickly go home. but i didn't feel scared. maybe that's the thing about shock. i don't know.

>> reporter: after losing her virginity to president kennedy on her fourth day on the job they began an affair, spending evenings together in the private residence as often as twice a week. you're 19. he's 45. what did you talk about?

>> we didn't have a lot of time to talk. he was the president. what we talked about was not world affairs . the president was boyish and playful with me.

>> reporter: in her book mimi calls their sexual encounters varied and fun describing the president as a sensualist who enjoyed being silly, especially in the bathtub.

>> he had a collection of little yellow rubber ducks . they were in the bathtub and rubber ducks became part of the game .

>> reporter: what did you do with the rubber ducks ?

>> we had races in the bathtub. he was not being president when he was with me.

>> reporter: no. definitely not. sometimes mimi would travel with the president, flying on the support plane in her role as press office intern. an one trip she said she attended a lavish party for the president at bing crosby 's house but she was mostly in the hotel waiting for the president to summon her. that's where you started the waiting game .

>> yes. waiting in the hotel room .

>> reporter: did you feel at all like i'm being used here? it's almost like you were a call girl to him.

>> i never felt that. now, looking back, i can see it's not a good place for a 19-year-old to be, in a relationship that's so imbalanced and with such a powerful person and an older man and at the beck and call. i see how sad it was. that is not how i felt at the time.

>> reporter: can you give me an example that would say to me this was more than just being a mistress?

>> just the way he was. the way he smiled with me. i feel that he did. he actually cared about me.

>> several teem tied to the jfk administration said she was an intern and had special access to the president. she didn't realize there were reportedly so many other women. she also talks about the fact that as much as she add miles an hour -- admired the president he had a dark side . she refers to his demons and i think there are things that will shock people.

>> meredith vieira , thank you so much for the interview and talking to us this morning. you can see meredith's full story on "rock center" with brian williams on its new day and time tonight at 9:00/8:00 central time here on nbc. also then after, mimi will be here for her first live television interview tomorrow here on "today."