jdrakeh said:
B. Must be self-contained in one book or core box set.
If you don't mind drinking two fingers of whiskey and squinting, you might just about squeeze GURPS Cliffhangers plus the free lite rules in under that. After all, if you get the free PDF version of the lite rules, it's only one book.

[But I must admit that I don't think the Lite rules work too well unless you either ban rifles or reintroduce the full blowthrough damage rules.]
I played a particularly enjoyable GURPS Cliffhangers game a couple of years back. I was a private eye based out of Berlin in the 20s, originally Swiss, ex French Foreign Legion, ex Mercenary, ex spy for the Bolsheviks during the Russo-Polish war (my big secret), now forced to work for a living again after losing all my wealth in the Great Inflation. I went chasing bandits around secret airfields in North Africa, in a duel of wits with the black sheep second son of an English lord.
What I enjoyed about this campaign was that it was a battle of wits, all about decision making and tactics and deception and covering the angles. I was playing a capable guy, but nothing implausible. I recently bought SOTC and whilst I'm a long term user of FATE and I like the mechanics, I don't like its genre emulation that much because I find it kind of silly. It's full of Gorilla emperors and jetpacks and it can't go two pages without mentioning Atlantis. It's full of "Pulp Science!", i.e. magic.
In the Cliffhangers game, when I needed to put an airfield out of operation I did it by sneaking up to the fuel dump, banging the guard on the head, and setting light to it. When I needed to kill half a dozen armed thugs I did it by silhouetting them against a burning building at dusk, while I sat in the dark three hundred yards away with a scoped rifle.
Of course, you might actually want all the not-quite-fantasy/supers stuff. The Cliffhangers book does cover that too, but I didn't really look at that side so I couldn't say much about it.