Detective Celcius Daly is plunged into an investigation that reveals Northern Ireland's darkest days aren't over yet. The body of a dead police detective drifts ashore at Lough Neagh. What appears to be a simple case of suicide, takes on a more sinister tone when Detective Celcius Daly travels across the Irish border to the desolate village of Dreesh, a place where law and order have ground to a halt, and whose residents, ruined by a chain of bankruptcies, have fallen under the spell of a malevolent crime boss with powerful political connections to the IRA. Out of his jurisdiction, out of his claustrophobic cottage and out of his comfort zone, Daly is plunged into a shadowy border world of desperate informers, drunken ex-cops, freelance intelligence agents and violent smugglers. Doomed to be kept in the dark by two separate police forces working in parallel to each other along a border bracing itself for Brexit, Daly's dogged search for the truth soon sparks an outbreak of murderous violence.