The novel is written in dialogue, with very little narrative. This means that you have to work hard to work out the plot. Higgins does not tell you. You are immediatly plunged into the world of a smalltime Boston criminal, Eddie Coyle, as he aims to buy guns for his bank robbing friends, gather useful information to pass on to the police, and stay out of prison for a drink smuggling charge. This seems like a tall order, as he is acutely aware. Previously, Coyle has collected an "extra set of knuckles", after his "friends" shut his fingers in a drawer and kicked it shut(retribution for selling traceable guns).
What is enjoyable about this novel is the sense of eavesdropping on an amoral world. The humour is deadpan and cynical. There is a constant sense of fear and paranoia. The impression that comes through is of the high price to be paid for a life of crime, in terms of mental peace.
Set in the 1970's against a background of student radicalism and racial tension, a bleak portrait of the country emerges. If you like Elmore Leonard, read Higgins to whom he owes an acknowledged debt. The recent film, Mystic River, based on a Dennis Lehane novel and again set in Boston, shares some of the grittiness of this world. It is not an easy read, but it is a thought provoking one.