The invaders are coming: the Posleen, a seemingly unstoppable horde who have conquered one star system after another, literally feeding on their conquests. Earth's dubious allies, the Darhel, have given the humans a number of highly-advanced technological devices, including a process for rejuvenating the aged, which has returned to service trained and proven soldiers who otherwise would be too old to fight. In the dark days after the initial Posleen attack, but before the primary invasion, the Chancellor of Germany faces a critical decision. Over the years, with military cutbacks, the store of experienced German military personnel had simply dwindled. After the destruction of Northern Virginia, he realized that it was necessary to tap the one group he had sworn never, ever, to recall: the few remaining survivors of the Waffen SS. Has he made a bargain with the devil, or is this a chance for the reviled SS at last to fight the good fight, and, perhaps, gain redemption? "Watch On the Rhine", is a new chapter, and a "side-story", in the best-selling Posleen War saga.