In 1940, Bailey was recruited by British military intelligence and assigned to Bletchley Park where a team of math whizzes was trying to crack Nazi transmission codes.
"My job was to take the de-crypts from the machines and take them to Hut 3 where the higher-up and big brains were," said Bailey.
The work of her Second World War group is now the plot of the Hollywood movie The Imitation Game.
One of the season's hottest films, the movie dramatizes the life of the brilliant but socially awkward Cambridge math genius Alan Turing.
Bailey remembers him well.
"He was inclined to talk in bursts, like you imagine that type of person would. But he had a lovely sense of humour and we got along very well," she said.
The movie tells how Turing created one of the world's first computers — a giant, floor-to-ceiling machine covered with hundreds of knobs and dials.
Bailey says she worked with it every day.
Tragic personal life
But Turing also had a tragic personal life.
He was gay when homosexuality was illegal.
Turing committed suicide in 1954.
In the movie, he's shown proposing to fellow worker Joan Clark, whom Bailey also knew well.
"She had an elongated box. I remember Joan said, 'That's what Alan gave me.' And, I remember, I said, 'What is it?' It was a pen and pencil set. That was what she got."
After the war, Bailey immigrated to Canada.
The code-breaking operation at Bletchley was kept secret for decades.
Working on a book
Only now, with the help of her husband Norman, Bailey is cobbling together her notes for a book.
She said her enduring recollection of Turing is of a man so many misunderstood.
"You see, he would chain his coffee mug to the radiator. And everyone got the idea, that's odd."
Pointing to a mess of wartime notes and documents on her table, Bailey said, "Now look at this table and see if you wanted to find a cup of coffee. You wouldn't have been able to find it, so Alan chained it to the radiator.
And, of course, he did that and everyone thought he was bonkers or something."
Bailey said the movie isn't entirely to her liking, but considering none of the people who made it where actually there, they did a pretty good job.
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