In "Treason," the chief of MI6 is poisoned at a holiday party, and Deputy Chief Adam Lawrence (Charlie Cox) takes over while he's recuperating. But it turns out the whole scheme has been set in motion by Adam's ex-girlfriend, a Russian spy, and she blackmails him into helping her. Meanwhile, both MI6 and the CIA are on his case as he tries to get out from under this tangled web. His complex story unfolds over the course of five episodes.
Watch "Treason" on Netflix.