Icel is becoming a warrior of Mercia, but King Ecgberht of Wessex still holds the Mercian settlement of Londonia and its valuable mint. King Wiglaf of Mercia is determined that the last bulwark be reclaimed from his sworn enemy to complete his rehabilitation as Mercia's rightful ruler. In the heart of the shield wall, Icel suddenly finds himself on the wrong side of the battle and thrust into the retreating enemy stronghold where he must take on the pretence of a Wessex warrior to survive and exact a cunning plan to bring down the Wessex force cowering behind the ancient walls. His allegiances are tested and the temptation to make new allies is overwhelming but Icel must succeed if he's ever to see Tamworth again and bring about King Wiglaf's victory, or will he be forced to join the enemy?
