When twin boys go missing from a playground on a local estate, Detective Inspector Sam Cree and her colleagues on the Norsey force in Essex are already overstretched. Then, a student and an elderly woman are shockingly gunned down and evidence suggests a sniper is at work. In the background of each murder is an unsolved crime but the choice of victims makes no sense. Is old fashioned revenge the motive or something deeper? Sam and her boss, Chief Inspector Bill Irons, face a race against time to find the missing boys and the killer before he strikes again.