Kate Henderson is on vacation with her children in France, visiting her estranged husband when she receives an unwelcome visit from an old adversary: the UK Prime Minister. A Russian agent has come forward with news that the PM has been the victim of the greatest misinformation play in the history of MI6. It's run out of a special KGB unit that exists for one purpose alone: to process the intelligence from "Agent Dante," a mole right at the heart of MI6 in London. Kate is forced back into the fray in a top-secret, deeply flawed, and dangerous investigation. As she works through the case, Kate realizes that while she is investigating MI6 for moles, they are investigating her.