Retromancer Gollancz Sf

the long version

There is big and evil magic abroad upon the face of the Earth. History has been changed: the Germans won WWII, America is a nuclear wasteland, and The Wife's Legs Cafe is serving Bratwurst rather than the proper British banger. To set it all right, the world needs Hugo Rune, a man who offers the world his genius, and asks only that the world cover his expenses. Hugo's job rewriting history includes a faithful acolyte, beautiful spies, advanced alien technology, killer robots, death rays, an ancient god and Hugo's arch-enemy, the sinister County Otto Black.