'Captivating and horrifying at once, a completely plausible evocation of the putrid morass that is the British Establishment and its craven capitulation to Russian money - or indeed, any money. Oliver Harris is squarely in the territory of the greats: Greene and le Carre but also the modern masters, Mick Herron and Adam Brookes. There can be no higher accolade' Manda Scott

How does a secret service confront its past, when its secrets must never be revealed?

Buried deep in MI6's digital archives is the most classified directory of all. It doesn't contain war plans or agent profiles, but shame: the misdeeds of politicians, royalty, business leaders and the service's own personnel.

There are seven decades' worth of images and recordings, usually acquired for the sake of assessing risk, sometimes as a guard against betrayal, often engineered by MI6 for their own purposes. They are the most sensitive two thousand terabytes of data in the Service's possession. When material from the archive begins appearing online, panic spreads through the Establishment like wildfire.

At first, the security breach only manifests itself in apparently random events: a suicide, a disappearance, a breakdown. But when it's discovered that the individuals concerned were all contacted by the same anonymous person, a connection comes into focus. The archive has been leaked. The hunt is now of unprecedented urgency before the entire political and business systems are fatally weakened. That's when they call for Elliot Kane...