Between 1939 and 1945, more than 10,000 people worked in Bletchley Park, the headquarters of the UK Government Code and Cypher School, tasked with breaking Nazi codes during War World II.
According to historians, the work done at Bletchley Park — now the subject of an Oscar-nominated movie starring Benedict Cumberbatch as British mathematician and codebreaker Alan Turing — shortened the war by two years and saved countless of lives.
It was here where a team of British engineers decoded Enigma, Germany's secret transmission machine, making it possible for the Allies to follow the enemy's moves.
Soon after the war ended in 1945 the facilities were dismantled, and the work done at Bletchley was made confidential.
Most of the devices built there to decode Nazi messages were destroyed. Most of the staff members returned to their daily life and faced serious consequences if they revealed what they had done during the war.
Bletchley Park's secret lasted three decades, while the site was transformed into a training school for members of Government Communications Headquarters, the British intelligence agency that remains in operation.
Only in 1974, when former MI6 officer Frederick Winterbotham published his book "The Ultra Secret," did the public learn about the site's critical role in history.
Many of the people who had worked at Bletchley were shocked. They had never been able to talk about the Park. They couldn't even tell their family.
Lady Marion Body is one of the those people. She worked on Japanese codes during the war and is among more than 40 women featured in the new book "The Debs Of Bletchley Park" by author Michael Smith.
On a visit to Bletchley last week for a press launch of the book, Body, who sat on a panel with six other women, said that after she left the Park she worked as a secretary in the House of Commons. In 1959, she married Tory MP Richard Body.
Body's husband was the first to tell her the secret was out. Here's how she recalls that moment:
I remember we could never speak about it and I had never done. One night, though, my husband had gone down to London for work and he had seen that book at Hatchards [a prominent British bookseller]. So he bought a copy and came back home with it, and that night I was sitting in the living room, and he came through the door and dropped the book on the desk in front of me and said: "Well, now will you tell me what you did during the war?"
And I just said: "No!"
Most of Bletchley Park is now a museum dedicated to educating the public about the codebreaking activities that went on there during World War II.
You can read more about Bletchley Park in Michael Smith's book "The Debs Of Bletchley Park."
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