The Poldarks look forward to life together in peace, but a plea from his old army colonel, Ned Despard, compels Ross to the capital. Arriving in London, he finds a city gripped with paranoia, and is determined to save Ned from the conspiracy that imprisoned him.

As George expands his power through a shady alliance, the Poldarks become caught in a deadly web.

George’s cabal moves to ruin the Poldarks, and Morwenna wrestles with a heavy decision.

Ross fights for Ned’s life as Demelza uncovers betrayal and the young lovers take flight for a future together.

Ross discovers a French plot, and George finds himself at the mercy of Joseph and Ralph.

With the fate of his nation in the balance, Ross must gamble everything to protect his country and those he loves.