Adam Lawrence immediately rises to the top of MI6 after his boss is poisoned. But a surprise meeting forces him to question his whole career.

With his family in fresh danger, Adam attempts to cut ties to his secret asset. Meanwhile, Maddy and Kara form covert alliances of their own.

In a bid to avoid treason charges, both Adam and Maddy go after Kara. But overheard conversations lead to big doubts about who they can really trust.

Adam flees London with the children after MI6 revokes his clearance. Before long, their hiding place is discovered - and blood is spilled.

More shocking secrets come to light as an unlikely team works to expose the truth, with lives and the very future of government hanging in the balance.