It's the life story of a stereotypical British officer type, portrayed as somewhat foolish yet likeable. We follow him from the Boer War, through the Great War to World War Two (though there is little in the way of action sequences). It was made during WWII. The main thrust of the film is that old-fashioned notions of British fair play must be set aside, and if the Nazis are to be defeated then Britain must "fight dirty."
It is about the passing of an age, a little nostalgic, but forward-looking, too. Also it is a love story of sorts, and a tale of friendship between men whose countries are enemies.
Oh, and it's a comedy.
Didn't go down too well at the time, possibly because it was a wartime film and it had such a sympathetic portrayal of a German, but more likely because it is just a little too offbeat and bizarre to succeed as a propaganda piece. Powell and Pressburger films are often a bit like that, that's actually what I like about them. More recently views about it have changed, and it's regarded as something of a classic.
Not to everyone's taste, though. Not by any means.
