The Mennym family faces its most awesome struggle yet when the family patriarch, Sir Magnus, predicts the unthinkable - that their world is about to end. Suddenly it's all change and the simple, hermit-like life of the rag doll family is galvanised into action as they prepare for their fate. Is Sir Magnus's astonishing prediction of doom just the pessimism of old age - or is this really the end of the line for the Mennyms?