Topher is planning a trip to London to visit a friend—but there have been bomb threats, which makes him worry. What's more, his beloved cat, Ka, has gone traveling again—and then, in the middle of a big bomb alert, Topher is called away—to a Saxon village threatened by Norsemen. Now he must get the villagers to heed his warning and foil the aggressors led by the terrifying Viking, Ingwar the Boneless, infamous for his cruelty and devious tricks. Can Topher save the village in time?