Frank Dillon retires from the Army after 18 years and struggles to adjust to civilian life. He tries to find a job, while trying to resist the temptation of the easy money offered by working for local gangland villain Barry Newman.
Frank and his team of ex-paras go to Scotland to tackle salmon poachers. When they arrive, they find that security is being dealt with by another ex-para, Tony Malone, the soldier whom Frank blames for the bomb explosion which killed six of his young recruits in Belfast.
Frank is stunned by the suicide of his military buddy Steve. The ex-paras form a company, Stag Security Car Hire. They are contracted to do a job for local gangster Barry Newman. Tensions mount between Frank and Jimmy.