England, 1616. Ex-magistrate Robert Belstrang, bored with country life, comes to London to investigate the strange disappearance of Thomas Jessop, son of a poor Catholic neighbour. He finds the youth in Bedlam asylum, silent and starving himself. But when he tries to free Jessop Belstrang finds himself the target of a dark plot to silence him… by any means necessary.

But Robert Belstrang is a stubborn man, and with the help of ex-soldier Daniel Oldrigg he sticks doggedly to his purpose. Their investigations take them deep into the fear-ridden Catholic underworld – where Belstrang soon uncovers a plan with its roots in the Gunpowder Plot of more than a decade ago.

The underbelly of London is a murky place, but Belstrang will strain every sinew to out the corruption... or die trying.