Johnny Innes, son of local politician Malcolm, is shot dead after interrupting one of his father's council meetings. Mike Jardine clashes with Malcolm Innes and is taken off the case but pursues his own line of enquiry. Embittered Liam Kennedy is a qualified sniper and therefore becomes a major suspect, especially as he has a grudge against both Innes and Jardine, one of whom, at least, will find their days are numbered.
A charred corpse is found in the burnt out remains of a clothing factory. Scott Dewar, owner of a rival factory, is the immediate suspect but Maureen Wishart reports her husband Derek missing and he not only worked for Dewar but had a knowledge of explosives. Meanwhile Jackie, still mourning Mike and watching her marriage crumble, finds her new boss Matt Burke difficult to get on with.
When teenaged prostitute Dee is found murdered Robbie goes gunning for Willie Strachan, a man whom he has long suspected of being involved in sex trafficking. However, he is not the only suspect as law student Craig Colhoune, son of a widowed sheriff who dotes on him, also finds himself in the vicinity with unexplained blood on his sleeve. And there is Mo, violent husband of reformed prostitute Sadie.
The apparent suicide of a sixth former at an elite boys' school turns into a murder enquiry and a journalist, much to the headmaster's displeasure, publishes an article linking the boy to drug-dealing before he too is murdered. A third body indicates a serial killer and the manner of the slaying leads to a famous painter.