They found her on the beach, frozen, like a statue carved in ice... Post-war Boston is down on its luck, and desperate to reinvent itself. But promises of a brighter future sound ever more hollow as the worst winter in recent memory tightens its grip. No one is interested in a string of murdered women - everyone would much rather pretend they don't exist. But the latest victim was loved... Old friends Cal and Dante are both struggling to find a way to live in a city that seems to be leaving them behind. The hunt for a killer gives them new purpose, as well as making them powerful enemies. But they believe in justice and second chances, and they will see this thing through - whatever the cost.

In 1950s Boston, the best way to survive is keep your head down and your mouth shut. But Cal and Dante prefer to do the right thing, not the sensible one. When a body is discovered tarred, feathered and shot, it is dismissed as a gangland killing. But Cal O'Brien's cousin, detective Owen Lackey, recognises the murder as the typical retribution for IRA informers. Owen knows that no one in the tight-knit Boston Irish community will talk. He turns to Cal and Dante for help, sending them into the city's shadowy underbelly. But there's a war on its way - and they're walking straight into the middle of it.

Two years after Cal and Dante destroyed the heart of the Boston Irish mob and splintered the Boston political landscape, everyone is out for themselves and trying to claim a piece of the city. It's early summer but already the city is in the grips of a heat wave, which doesn't help tensions any as the fractures within Boston's underworld are finding their way to the streets in payback shoot-outs between mobsters and the police. When a body is discovered at the Charlestown locks, tarred and feathered and shot, it appears to be a gangland killing, and almost immediately dismissed. But Cal's cousin, detective Owen Lackey, who intended to intercept a boat coming into Boston weighed down with stolen guns and ammunition, recognises the murder as typical retribution for IRA informers and knows that with this murder there may be much more at stake than his superiors realise. Keen to uncover those responsible, he asks Cal and Dante to help search the Irish-American enclaves of Dudley Square, Dorchester and South Boston for some sign of the killers. It is a journey that will take them into the shadowy parts of Boston, a world of packed dance halls, Irish wakes and funeral parlors, of down-and-out immigrant rooming houses, bars, and secret meeting halls, and, ultimately, to the discovery of a terrorist plot that will shake the city to its core and bring them head-to-head not only with Cal's past but with the IRA Army Council itself.