In the late summer of 1834, a near derelict schooner runs aground on the east coast, opposite Chesapeake Bay. On board are hundreds of dead bodies that have died while fighting each other. The coffin ship is sensed by a young girl, Mary who convinces her father to go and find the vessel. Leaving Mary, who refuses to leave he goes for help. Upon his return, he finds Mary possessed by whatever was on the schooner. Captain Bardeen, Provost of Newport is called. The sight of so many dead bodies, killed in such a vicious way, hits home with him. Mary escapes, leaving a trail of death behind her. She is pursued by the Captain and two men. He finally catches up with her and kills her. As she dies a black cloud, a miasma, is released from her body, and enters the atmosphere. Suetonius Paullinus, was the Roman general responsible for the virtual annihilation of the Druids. Only a few managed to escape to Eire from the massacre on Angelsea. They took with them their hatred of the Romans and the essence of those who died. Banning the Druid carries the souls of those massacred by the Romans within him. His task is to kill Romans, and too him everyone is a Roman. A miasma descends over a revival meeting in Savannah. Those on Revival Field feel an overwhelming urge to kill Romans, and to them, everyone is a Roman. Hundreds lay dead on the field. Captain Bardeen is called upon by Major Fothergill of the U.S. Army, and together they try to understand what has happened. The miasma falls over the Five Points area of New York, and another massacre takes place. Fear begins to stalk America. Banning comes to the ground, taking over the bodies of those chosen, and kills Romans. With the situation escalating the president, Andrew Jackson becomes involved offering the captain and the major his help in understanding what is going on. They establish a base in Washington and are soon inundated by those who have a knowledge of the druids and druidic culture. The Irish, in particular, are desperate to help as they are being blamed for what is happening. Lady Catherine, fallen nobility from Eire and a druid with the ability to speak ancient Gaelic, the language of Banning, joins the team, as does Breana, a young girl who can sense Banning and his thoughts. New York is set aflame when the local gangs decide to attack the Irish. This riot sparks similar occurrences across the United States. Banning kills at will, and news of his atrocities and the randomness of his attacks spread, as does the fear. Breana gradually makes contact with Banning, but it is a slow and frustrating process. Lady Catherine teaches her the ancient Gaelic that Banning speaks. Over time a rapport, of sorts is established, and the motivation behind why Banning acts like as does is revealed. Meanwhile, the massacres continue. West Point where Banning changes his tactics and commands his army to act in units. He comes to ground and learns to use a gun. The biggest massacre takes place in Boston. It becomes apparent to Captain Bardeen and the team around him that there are two Bannings. One is the druid who hates Romans, and the other is Banning the man, a more considered and knowledgeable person. It is this Banning they try to reach. It takes time, but, eventually, he takes over the body of Major Fothergill and talks through him to Lady Catherine, who longs to join with him. Banning tells them that the situation can only be resolved at the Cromlech, the standing stones in Angelsea where the druids were all but exterminated. Captain Bardeen, Dai, and Lady Catherine voyage across the ocean to Liverpool before making their way to the Cromlech. Banning takes over the body of Dai, and together with Lady Catherine, they enter the circle. Dai slowly recovers, but Lady Catherine is dead. Her essence has joined with that of Banning. Captain Bardeen returns to Newport where he finishes his journal. He writes and presents a copy to the president should Banning return.