A Robert A. Heinlein classic reissued with an all new celebrity forward by noted Heinlein biographer Bill Patterson and afterword penned by three-time award-winner for fan writing and science fiction scholar John Hertz. It’s a cross-time fight for freedom as a family retreats to a bomb shelter during a nuclear attack – only to emerge hundreds of years in the future, thrown forward in time by the blasts. There lifeboat ethics rule as they struggle to survive...until they’re discovered by up-time humans, the survivors of the apocalypse. These survivors are of African descent. Down-time humans – in fact, all of the European-descended – are held guilty for the state into which the world has fallen and designated as automatic slaves. The only escape is to find a way back down-time, to change events sufficiently to make absolute certain this nightmare future never get a chance to in the first place! "Not only America's premier writer of speculative fiction, but the great writer of such fiction in the world." – Stephen King. "One of the grand masters of science fiction." –