Mother Dolores Hart, the woman who left her movie career to become a Benedictine nun, has released a new biography explaining her shift from a rising star in Hollywood to life as a cloistered religious.

"I have used the analogy of falling from a 20 story building because that's what I felt like the first night after I entered," Mother Hart told CNA May 6.

When she was approached by her life-long friend Richard DeNeut some 10 years ago about the possibility of writing a memoir, she feared that she would have neither the time nor the memory to write all "the wonderful things that happened" into a book.

However, DeNeut insisted saying that her memoir would be "very good" and "very important" for others to read.

The friends began speaking for about an hour each day over the phone and Skype to get her story on paper and eventually they had enough material for a book.

However, they ran into difficulty when many publishers wanted to start the book with her role in "Loving You," the 1957 film where she gave Elvis Presley his first on-screen kiss – which would have left out details of her turbulent upbringing and childhood conversion to Catholicism.

Eventually the pair turned to Ignatius Press, the California-based Catholic publisher because they "promised they would stay honest" to her story, Mother Hart said.

"We didn't do it because they were a Catholic publisher," she said, "mainly because they made that promise."

When she entered the monastery in 1963, the 24 year-old actress shocked her friends, family and the rest of Hollywood. The then-actress was engaged to be married, had a multi-film contract with Metro Goldwyn Mayer and was pulling in $5,000 a week.

However, her heart kept going back to the Abbey of Regina Laudis, a Benedictine monastery in Connecticut founded by French nuns in 1947 where she visited for retreat during her time on Broadway in her Tony-nominated performance in The Pleasure of His Company.

"In my mind's eye my desire to enter the monastery was to find God," she explained. "Well, God wasn't waiting for me on the other side of the door – in certain ways, he was, but not in the way I had imagined."

One evening after an engagement party, her fiancé, Don Robinson, sensed that her heart was with "something or someone else" and told her she needed to settle that before they were married.

"It was something that had been gnawing on me, the thought that maybe this was something I should do," she said.

Hart packed her bags and left Hollywood for Connecticut where she met with the Mother Abbess to seriously discern the possibility of her vocation to the religious life.

"It was very clear before I left that what I had to do was enter the monastery because that's where my heart was," she said.

During that time, another Catholic actress, June Haver, had made headlines when she become a postulant with the Sisters of Charity in Kansas, only to leave after just a few months.

In order to avoid the publicity, Hart was instructed to keep her decision quiet until she actually entered.

"It was a horrible time," she said. "I couldn't accept any contracts, I couldn't accept to do anything, I couldn't tell anyone anything."

Although she had made the decision to enter she continued to wonder, "Is this really going to be the answer?"

"I left the world I knew in order to reenter it on a more profound level," she writes in the book's preface.

"Many people don't understand the difference between a vocation and your own idea about something. A vocation is a call – one you don't necessarily want. The only thing I ever wanted to be was an actress. But I was called by God."

Some 50 years later, Mother Hart is now the prioress of the Abbey and looking back, she realizes how she's been able to use the gifts that God gave her which made her a successful actress, namely listening.

"I never would have thought that except when I really got into (acting) and found out that a good actor or a good actress really has to listen first of all to the character that you have to portray," she said.

"When I did finally come to Regina Laudis, I was touched by the fact that the first words of the Holy Rule of St. Benedict read, 'Listen my daughter, my son, to the voice of your Master with the ear of your heart.'"

Mother Hart explained that "religious life" as some may assume, "is not leaving your gifts at the door and coming inside to find God in some mystique."

Rather, she said, "A community brings its gifts with you and serves one another with what you have."

"The Ear of the Heart: An Actress' Journey from Hollywood to Holy Vows," by Mother Dolores Hart and Richard DeNeut releases May 7 from Ignatius Press.