England, 1688. A deadly conspiracy. A crown under threat.

King James II finally has a newborn heir, but across the country rebellion is stirring. Rumours fly about the child’s legitimacy. And strange symbols of an upside-down crown appear on the streets of London.

Amidst the turmoil, Whitehall official James Marwood and his wife Cat, an architect navigating a man's world, have built a precarious life for their three children. But when a dead body is discovered and a treasonous pamphlet begins to circulate, they are all hooked into a dangerous conspiracy.

Who is risking everything to paint sedition across London’s walls? What secrets are being killed over, and what lies spread? In the face of a deadly plot, does survival matter more than the fate of crown and country?