After the destruction of the Roman army in Hibernia, Commander Darius Lucilius is taken prisoner by Fionn, a newly crowned Celtic king. Darius's only desire is to return to his people, yet he finds himself increasingly captivated by the beautiful, dangerous Fionn, and caught up in the strange politics of a foreign and ancient world. Meanwhile, Fionn has plans of his own for Darius. As the two men navigate the fragile trust building between them, Hibernia dangles on the edge of a new war. If he hopes to survive, Darius will have to work out where his loyalties - and his heart - truly lie.