Life was very ordinary for ten-year-old Robyn Silver. The often-ignored middle child in a big family, the most excitement she had was the dash to the dinner table to reach the last slice of pizza. Until... she begins to see creepy creatures around her town - creatures that are invisible to everyone else. And when her school is forced to decamp to mysterious Grimdean House and she meets its equally mysterious owner, Mr Cryptorum, Robyn finds herself catapulted headfirst into an extraordinary adventure - with more excitement than she could possibly have imagined. Be careful what you wish for...