I recently got saw the Imitation Game on recommendation, and I've searched this sub for Alan Turing questions already and found two or three threads about it with various criticisms of its historical accuracy, etc. One thing that stood out to me as odd though, is that he's portrayed with pretty much the exact same personality as every other smart man on television or in movies - somewhere between a stereotype of a person with an ASD and Dr. House. One person on one of those threads mentioned that this was inaccurate as well, and from my recollection of it, Turing's portrayal in Cryptonomicon (which I realize is also not historically accurate, since it's fiction) was also quite different. There's a lot out there on his work and his contributions to computer science, but I'm curious about what he was actually like. Is there good information on his personality out there? I mean, it wasn't that long ago.
You can read Turing's accessible paper Computing Machinery and Intelligence online (but you have to skip over some OCR errors). This is the paper that introduces the famous 'Turing test'. I think it shows a man of wit as well as intelligence, and somebody acutely aware of interpersonal relationships, contrary to the portrayal in the film.
There is very little direct evidence of Turing's inner life: no diaries, few letters and only a few formal mathematical papers exist. However it was possible until recently to interview his contemporaries and gather their opinions of him, and make a construction based on all the available evidence. This was done first by Andrew Hodges in the late 1970s and early 1980s. Nearly all subsequent sources are at least partially derived from his work, first published in 1983.
It was written by a gay mathematician about another gay mathematician in a time when consideration of sexuality in a scientific biography was controversial, and for that reason Hodges went to great lengths to justify every assertion he made, and separate historically-verifiable assertions from his extrapolations, though they were well-informed from his research.
Despite any publicity, the Imitation Game film is a work of fiction (there is a disclaimer at the end of the titles which instructs that nothing in the film is to be taken as true). Historical veracity was sacrificed in order to tell the story that the scriptwriter wanted to tell.
The biography on which it is based, however, is an attempt to answer your question in a properly scholarly and well-referenced way. The author maintains a website here which contains information from which you can draw your own conclusions.
For a proper in-depth answer, the book is available in all the usual places and is a thorough attempt to answer your question in the fullest terms available.