Mariella Mystery (That's me!) - totally amazing girl detective, aged 9 and a bit. Able to solve the most mysterious mysteries and perplexing problems, even before breakfast. It's the week before Hallowe'en and the citizens of Puddleford are being terrorised by a strange fog. People caught up in the fog experience such unnerving hair problems as extreme frizziness, wild, uncontrollable volume and shocking colour transformations for days afterwards. Just what is going on? It's up to the Mystery Girls to find out - before the huge hair scare gets even bigger...