Having finally escaped from the underground Queendom of Claire in book two of this series, Sir Seth and Sir Ollie eagerly head home — but soon find themselves in yet another land: the snowy Ah Ah Kaachu, a sleepy place that lives in the shadow of a giant mountain.

Of course, this new land has its own plagues and problems. Specifically, a frightening Yeti named Betty, who threatened the inhabitants with a devastating avalanche ten years ago. They've already moved their town once to escape destruction — now, as the snow stirs once again on the Yeti's mountain, it appears that not even the new village of Kaachu is safe.

And, as the friends get separated in the wake of yet another avalanche, their mission becomes a two-pronged race against time — one knight hurrying to warn the village of the worst avalanche yet, the other fighting to bring old enemies together to vanquish a newer, and greater, foe.