The Hollow Boy, by Jonathan Stroud

Successful psychic investigations mean Lockwood & Co are overwhelmed with cases dealing with recalcitrant ghostly phenomena. This is exacerbated by a huge outbreak in Chelsea soaking up the resources of the major agencies. Taking on efficient Holly Munro as admin manager makes work go more smoothly, but she is the diametric opposite of Lucy and the two girls clash. Lucy’s particular psychic sensitivities are also causing her problems, creating dangerous distractions in the field as they develop. This third book of the series sees the Lockwood team navigating its own internal friction and dealing with the broader politics and economics of the ghost fighting industry and its shifting alliances while struggling for a secure place within it. The tricky relationship between Lucy and Anthony Lockwood puts the whole team at risk, leading to a big decision for Lucy that will dramatically affect the future of the agency. Smart, funny and scary, Stroud’s Lockwood & Co series operates on several levels. Each fast-paced teen mystery is underpinned by a complex world and punctuated with clues to an overarching conspiracy that promises a satisfying eventual conclusion.