Valkyrie Cain hasn't had an easy life, she's been named all sorts of horrible things such as 'death bringer'- the one to destroy the world. For seven years Valkyrie has been training herself in a number of combative arts and disciplines of magic, working on cases with Skulduggery Pleasant (the skeleton detective) and basically making trouble for the sanctuary as per usual. However it's time to tell her sister, young Alice, not everything is as it seems and Valkyrie feels she should 'grow up' to start teaching her sibling about all the wondrous things a life like this can include. But with her evil side slumbering inside her - better known as her 'mood swing' and 'Darquesse', how long can all this disgusting 'maturity' last?... Really?