Billed as the conclusion to the present trilogy (following Colonization: Down to Earth, 2000, etc.), which itself is a direct sequel to a tetralogy (the Worldwar yarns) about the invasion of Earth in the middle of WWII by the dimwitted, lizard-like Race: from an author who's built several other skyscrapers out of alternate history (the Great War series, etc.). Here, during the alternate 1960s, the Lizards must face the fact that they can hold the planet Earth only by dint of superior firepower and overwhelming numbers. If you can't remember who's who, or what's been happening through the six preceding volumes—not to worry: Turtledove's patient recaps and updates will keep you in the picture. The only question remaining to be settled is: Will Turtledove stop here? Don't take bets.