Weird things start to happen almost immediately after their arrival and Magenta finds herself unable to ignore the spooky events at the castle - 'possessed' teachers, a secret tunnel, strange whisperings and the forbidden tower...This book tells the tale of the Legend of Horiblissa and of Magenta's endeavours to unravel the mysterious incidents that are happening at Oribliss Castle, whilst up against the school bullies, led by the spoilt brat Alwin Simpson-Slithers.