The cracked the ENIGMA code with a machine called Bomba Kryptologiczna.
Polish mathematicians are the ones who originally cracked the ENIGMA and then both the polish and French cryptanalyst turned all of their information over to the British before Germany invaded Poland in 1939.
the machine is known as the Bombe. Using their new machine, they were able to break complicated Navel ENIGMA systems. (helped the Allies avoid German U-boats during the Battle of the Atlantic.)
Unfortunately, the Germans increased their security and started changing the cypher daily. Alan Turing and Gordon welchman created a machine to relieve some of the pressure from the code breakers.
When the British finally cracked the code they started sending The Office of Strategic Services (OSS/CIA) information on foreign military and sabotage activities. ULTRA, which was the code name for all information coming from Bletchley park, was one of the few sources to give such delicate info. Turing soon went to America and showed US military intelligence how to use the Bombe and his knowledge of the ENIGMA. Turing wasn't happy with how the U.S. was treating the bombe like a machine and not a brain.
The 19 year old Arnold Murray first met Turing in front of a movie theater in 1951, and the two of them met up multiple times after that. In the year 1952, Turing's house was broken into. Murray went up to Turing and admitted that the person that broke in was an accomplice of his and Turing went to the police. While the police were investigating, Turing informed them that Murry and him had had sexual relations in the past. At the time this was highly illegal, and because of this the two men were charged with gross indecency. Turing went on trial and pled guilty and he was convicted.