A chilling event at the Royal Edward hotel on the night of Assistant Chief Constable, Alison Vosper's leaving do forces Grace and Branson into a difficult position when they must investigate all hotel guests, including high ranking East Sussex police attendees.

Something about the incident is causing a deep unease in Grace - he knows he's seen this before. Has a sinister offender from Grace's past dubbed the Brighton Prowler resurfaced or is this a copycat?

As the attacks continue, Grace is convinced it's the same man - and delving into the past may be the key to saving the next victim.