When ACC David Mallory and profiler Fiona Nightingale investigate three murders with a sinister connection, they release a dark evil that has been lurking in the depths of The Ring - a decade-old paedophile scandal that still haunts the city. Anger Man emerges from the shadows to avenge the victims of The Ring. The only person who can stop him is Mary Longsdale, a patient in a mental hospital, but she suffered terrible abuse as a teenager and opening up The Ring has cracked her fragile personality. As Fiona Nightingale struggles to overcome Mary's demons she uncovers a tragic love story. Meanwhile, Mary is forced to betray the only person she ever cared for...and Anger Man plans one last spectacular killing spree.