It seems that people on IMDb didn't like this. I did. I thought it was about a lot more than Alan Turing being gay, and I appreciated seeing this after seeing "The Imitation Game." People keep saying they want more science. A lot of it would go over people's heads.
It states right in the documentary that what made Turing a genius was the fact that, although others had broken the Enigma code, no one had ever broken the German navy code. Turing built a machine to do that. He also invented the idea of the computer years before its time, even talking about taking a computer to the park, like a i-phone. The documentary also shows some of his early inventions.
The documentary's conceit is that Turing (played here by Ed Stoppard) is talking with a psychiatrist (Henry Goodman), as he goes over his life. There are interviews with the woman to whom he proposed, Joan, with the psychiatrist's daughters, Turing's nephew, and others.
I think we learn more about Turing than just that he was gay. That he was gay is important because after serving his government and, according to Churchill, shortening the war by two years, he was chemically castrated. Pretty shabby treatment. The estrogen had an effect on his brain as well. And we know what happened in the end. A sad statement about the way heroes are treated.
I think this is a good companion piece to "The Imitation Game," and I recommend it.