Fran returns from a month at camp to find her family, and nearly everyone else in London, dead of a mysterious disease. The city is walled off, streets are deserted, and there's nothing on radio or TV except bland warnings and old movies. Fran finds her best friend Harry still alive, and also Shahid, a formerly remote classmate; the three strike off across town, but Harry, fretful and irresponsible, soon runs off, while Shahid falls ill. Unlike John Christopher's Empty World, which has a similar premise, this focuses more on character than on plot; switching between narrative and diary entries, Ure explores Fran's inner turmoil as she reluctantly changes from dreamy homebody to leader, and Shahid's as he loses some of his adolescent arrogance. Was the plague released deliberately, or accidentally? Neither the characters here nor readers ever find out. After several weeks, Shahid recovers and the two leave London, not knowing how far the devastation has spread. The loose ends make the story all the more chilling. (Fiction. 12-15)