The Imitation Game is a fascinating look inside the world of codes and code breakers laid over the sad, tragic story of the lead cryptographer Alan Turing (Benedict Cumberbatch).

In World War II, the Nazis developed the “Enigma” machine which created a code that seemed impossible to break. They were able to sink ship after ship in the Atlantic, as well as advance throughout Europe on the ground.

Knowing they had to break the code, England’s intelligence community created a group of people to try and break the code. Turing, a mathematician and professor at Cambridge, easily passes the test. He is thrown together with Hugh Alexander (Matthew Goode) and John Cairncross (Downton Abbey’s Allen Leech) and he finds he has no people skills.

When Turing announces he wants to create a machine that will do the thinking for them all, the other scientists are skeptical and try to get rid of him with the willing help of Commander Denniston (Charles Dance). Turing knows he is on the right track but at the same time he has a secret that, if it got out, he would be summarily dismissed from both the codebreaking job and his post at Cambridge.

He was gay, a major crime in England until 1967.

Turing did manage to make a friend of MI-6’s Stewart Menzies (Mark Strong) who sees the brilliance hiding inside the bumbling scientist. Menzies allows Turing to hire a few more folks and Peter Hilton (Matthew Beard) and Joan Clarke (Keira Knightley) join the team.

It takes time and many stops and starts but eventually “Christopher” the machine starts to think. Since Enigma changes codes at midnight daily, it must be reset at the same time. As weeks roll by with no results the pressure starts to build.

When they at last crack the code, they have to deal with deciding how much to information to release. To stop the Nazis everywhere would alert them the code has been cracked and it was time to create a new one.

The Imitation Game is a first-rate thriller and grabs your imagination from the beginning. Turing’s past, and this story, is told in flashback. When Turing called the police after a break-in, they start digging into Turing’s past and he is arrested for being gay.

Instead of going to prison, Turing agrees to chemical castration. He committed suicide in 1954. Queen Elizabeth II pardoned him in 2013.

The fact the Enigma Code was broken was classified for over 50 years after the war.