With Nemesis Roth leaps back again, to Newark in 1944, in the summer, polio season — but this year, the worst outbreak of polio in a lifetime, and long before there was even a glimpse of a vaccine. The fact of the eradication of polio, an affliction unknown in the lifetime of most Americans now, only makes Roth's recreation of the disease all but horror-movie immediate: unstoppable, unpredictable, unknowable, evading diagnosis until it is too late, with cases spreading through a neighborhood by the hour and children dead overnight or consigned to an iron lung for the rest of their lives (and what is an iron lung, any reader might have to ask, only to find out, and then be horrified at how polio could redefine everyday life?).