Meet Matilda Stubbs. She's nine months old, has six new baby teeth, and loves to send spoonfuls of porridge catapulting through the air. But this is no ordinary baby: Matilda is also a Mallockee -- one of the most powerful creatures in the world. And guess who her big brother is.

In his third heroic adventure, Measle is thrust into his most outlandish predicament yet. How will he ever escape from the spooky, deserted castle, fend off his guardian Wrathmonk, rescue his kidnapped parents, and look after his baby sister? The odds are stacked against him until he learns that, this time, he's got a powerful ally -- Matilda the Mallockee is on his side.