Topher is planning a trip to London to visit his friend Ellie - but there have been bomb threats, which makes him worry. What's more, his beloved cat, Ka, has going travelling again.

Topher doesn't want to lose her. And sure enough, 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?