Rat Poison — Margaret Duffy

When vicious gang warfare breaks out in the city of Bath, it soon becomes apparent that a London crime lord is trying to move in to the area. DCI James Carrick has to enlist help from the Serious Organized Crime Agency. Patrick Gillard, late of MI5, and his colleague Ingrid Langley are brought in, and their first task is to try to identify those taking part in the shootings. But the gang seems able to stay one step ahead of them all the way...