Summer 1604: England is on edge, as a high-powered Spanish delegation arrives in London to start vital and long-awaited treaty talks. King James, a year into his reign, wants to be seen as The Peacemaker King, bringing an end to nearly twenty years of warfare with Spain which has left both countries exhausted and almost bankrupt. Yet there are those who profit from the war – and such people cannot be allowed to threaten the peace negotiations.

This puts extra strain on the king’s powerful minister, Lord Cecil, which is why Marbeck finds himself working for a new spymaster, charged with the role of protecting the Spanish party. But even Marbeck hasn’t foreseen that the task will pit him against corsairs of the high seas, double agents and corrupt noblemen who will stop at nothing to wreck the treaty, forcing him to face his biggest challenge yet…