How Based On A True Story is The Imitation Game?

Rob and his little brother Tim break the code or some other such pun on The Imitation Game! How true to life is the story of Alan Turing and his time at Bletchley Park breaking the Nazi enigma code and saving the world?

Where to watch The Imitation Game: https://www.justwatch.com/us/movie/the-imitation-game

Alan Turing: The Enigma: The Book That Inspired the Film the Imitation Game - Updated Edition (Revised) by Andrew Hodges: https://bookshop.org/a/4479/9780691164724

The Code Book: The Science of Secrecy from Ancient Egypt to Quantum Cryptography
by Simon Singh: https://bookshop.org/a/4479/9780385495325

Further Reading / Watching:

Two part video explaining how Enigma worked:
https://www.youtube.com/watch?v=G2_Q9FoD-oQ
https://www.youtube.com/watch?v=V4V2bpZlqx8

More about Enigma and Turing:
https://www.youtube.com/watch?v=d2NWPG2gB_A
https://www.youtube.com/watch?v=kj_7Jc1mS9k

Info about Welchman and traffic analysis:
https://www.youtube.com/watch?v=mXZNayEPFKc

A lot of similar info from the videos above but at 3:20 there's a good shot of the Enigma rotors taken out of the machine:
https://youtu.be/ASfAPOiq_eQ?t=201

Good recap of how BOATS:
https://slate.com/culture/2014/12/the-imitation-game-fact-vs-fiction-how-true-the-new-movie-is-to-alan-turings-real-life-story.html

5 min video explaining the basics of Turing Machines: https://www.youtube.com/watch?v=dNRDvLACg5Q

Videos on Colossus, the computer Tommy Flowers designed that broke the harder Lorenz cipher:
https://www.youtube.com/watch?v=9HH-asvLAj4
https://www.youtube.com/watch?v=7cDeG3hyraA
https://www.youtube.com/watch?v=knXWMjIA59c