That certainly was a great movie but it made it look like the British broke the code all on their own.
- The Brits did a lot of the work including refining the technique but they got a lots of help initially from Polish exiles and then later from the Americans.
(I wonder why the Poles were trying to crack German code before the WW2?
)
The other really big "crack" was the Japanese WW2 code system and you guys did that on your own. You get some idea about it from the new movie "Midway". If you haven't seen Midway I'd highly recommend it but it's worth doing some reading about the battle and what lead up to it before watching the movie. It also benefits from multiple viewings.
https://slate.com/human-interest/2013/11/u-s-in-world-war-ii-how-the-navy-broke-japanese-codes-before-midway.html