Maggie Black is settling well into life after being a government assassin. Finally content and deeply in love with her partner Leon, she is ready to open her own secret agency where she can put her unique skills to use and help those in need-on her own terms. Getting out isn't as simple as Maggie had hoped, however, and her past comes back to haunt her and put a stop to any plans of a fresh start. Nina, an old colleague-turned-enemy is out for blood and returns from hiding in the most devastating way possible, shaking Maggie to the core and ruining any chance she had at happiness. Blinded by grief and overcome with rage, Maggie sets out to put an end to their rivalry one way or another. Tracking her enemy from the rural moors of Ireland to eerily familiar haunts in Russia, Maggie is on the warpath and hellbent on revenge. But she must be careful and not let her emotions overwhelm her, because Nina is back in full force, and she hasn't come alone...