Its world war two, codes need to be cracked, and Alan Turing has changed his name to Tom Jerico and stopped being gay. So, what we are left with is a spy thriller, where the star is a mathmatician - more inexplicably a mathmatician women are attracted to... but I'm told people are strange in Milton Keynes, so thats OK then.
At best the plot is competent - nothing unexpected happens, but theres nothing special. My own interest was held by the historial accuracy - and they did a good job - there was nothing I missed, or felt was handled badly (except for a minor note that every time someone said "plain text" they pronounced it "plaintext" even in contexts where "plain text" would have been more appropriate.
Dialogue is better - not Stoppards best, but certainly above run of the mill Hollywood. As ever with Stoppard, there are a few moments of brilliance, but these get lost (as does everything else) because too much is trying to be packed into too short a film - theres a war film, a spy thriller and a romance all competing for space.
Its probably sad to admit it, but what made the film for me was the sensative handling of the codebreakers - all socially inadequate, but not used for comedic purposes - rather they are used to show the contrast between the military's nature, and the cryptographer's nature. Its also telling that most of those people can be found by wandering down a street in Cambridge
All in all, the film works - its professional and gripping. There is nothing really outstanding, but enjoyable and of higher quality than most of the rubbish in our cinemas these days.
I think four rotors out of a possible five would do enigma justice... it might even me a good enough rating to make Dougray Scott break out of his northen accent.