After the death of a beloved sister, Wyatt King's only plan is to be left alone with his grief and his new ward, his days-old niece, Hannah. But when you're the last demon hunter descended from a centuries-old line of demon hunters, others might have something else in mind. When Hannah is kidnapped by Malik, the second in command of Hell, Wyatt is rattled to the point of inaction, until an otherworldly ally guides him to an ancient stone circle: a gate to Hell. Soon Wyatt finds himself protecting - and falling for - the only clue to Hannah's whereabouts: a succubus-turned-human named Meridiana. Both Wyatt and Meridiana are stalked by Malik, who wants Lucifer dead and believes the couple has connections to an Archangel, the only creature powerful enough to kill Lucifer. Can Wyatt and Meridiana stop Malik from succeeding in his plan to take over Hell? Can they save the world from certain doom?