First, it's the electricity that goes off, so Nick and Binky, coming home from school, have to walk up the ten flights to their apartment. Then, Mrs. Piggott, who ""does for"" the Lorimers, is there briefly to greet them, not their mother; and by the next morning she still hasn't come. (Unbeknownst to them, she's unconscious after an auto accident.) Clutching at normalcy, Nick--usually a dreamy, drifting thirteen to Binky's assertive eleven--decides they should go into Sydney to school, only to find the building empty and a single teacher waiting with the news he didn't listen to yesterday: that utilities and transport workers have gone on strike to protest the nearby construction of a nuclear power plant, an action ""in the interests of all."" Quickly the ordinary turns ugly as fuel, water, and food supplies dwindle; apartment-dwellers leave for the country; dogs form into packs, looting breaks out, rats and scavenger birds appear--all within a few days. Meanwhile Nicky and Binky, whose father is abroad, seek out the Piggotts to flee with: someone has to tell them how to do things. En route they pick up Digby, a rough-and-ready youngster, and his adopted dog Tilly, who complete the curious, poignant traveling-party. Jo Piggott, old, crippled, nobody's weakling, rides in an auto trailer pulled by the two boys, while Mrs. P. and Binky push from behind and Tilly bounds alongside. But though Jo rallies to see them through the decaying city's horrors, Mrs. Piggott worries about his occasional absent look, his way of slipping off into the past. And once the strike has come under control and the party has reached safety, he drags himself to a tree with a distant outlook, and dies. It's a large book, however brief, balancing fear and excitement and fellow-feeling, that the contrivance of the mother's accident doesn't diminish--the larger, indeed, for the insignificance her absence comes to assume.