The Exile is book three in the Christian sf (alternate history) series The Interregnum, set on Ortho-Earth (Greater Hibernia) during the sixty-year ban on the throne following the 1941 deposition of James IV, High King over two of the six Timestream earths. The action of this volume takes place on Hibernia and Tirdia (Prime), with arcs of the story cycle rotating among several accounts, some continuations of those in previous volumes, others introducing new characters to interact with the familiar ones.

Hibernia: Sean Reilly, now Donal XII works with his former MP Captain, now General Jack Graham to put down a rebellion in Afghanistan that has a nasty potential to become a new biological war. Also anxious to develop a new cadre of officers loyal to the throne and Tara's ideals, he cynically manipulates several lives, particularly those of promising female officers. One of these is Mara, who plays a key role in the Afghanistan campaign. Others include Colin and Daisy Kildare, and childhood friends Maeve Derry and Cath Maguire, who have their own agendas for the day when the throne and crown might again be claimed.

Katherina Rourke (a.k.a. Karina Tansey and Rosie Bolivar), still not over her love/hate relationship with Sean, is released from years of solitary confinement at Prison City when old enemy Thomas Monde becomes governor. Shown that she cannot escape, she does anyway, only to find herself in Sean's office being made an offer she cannot refuse, if only she will allow herself to be recaptured.

Her adoptive daughter Sheana, who runs into the bush when Karina is first captured, survives briefly on her own, then joins the bards on tour for marvelous adventures, particularly at Bardsbridge near Glenmorgan, where she rescues her beloved teacher, the famous but anonymous scholar Rhiannon. After a stop in Edwardston and an exciting episode with Meghan (Mara) and Rainbow, she returns to Australia, where an overheard conversation sets her running again. Later, she is taken in by released convict, now born again Christian Bria Desmond, and is raised by her until Bria dies. Finally, she meets Friends Daisy and Colin Kildare, joins their school, and wins high honours.

Tirdia: Meanwhile, Day MacAllister grows up with mysterious guardian Angus on isolated Sangster Island in the Georgia Strait near Vancouver, BC, on alternate earth Tirdia. He teaches Day skills and knowledge (including a Gaelic language) that have no part or place on their version of earth. Both have to come to terms with betrayal, death, and their own inadequacies as they find or renew faith in God. At first believing Angus mad, Day is forced to realize there really are other earths when the conflict between Angus and clan Campbell comes to their doorstep and Day must enter the fray, first on Tirdia, then on Hibernia.

Hibernia: Yet another arc of the story cycle tells of Maeve and Cath, who, with their friend Cole Culchaine, made Kilkarney's class of 1989 almost as famous as an earlier group of friends made that of 1968. The arcs of the story cycle join and close (for this volume) at Monaco, where Cole and friend Dai investigate a mysterious conspiracy whose roots tie to both the Tirdian aspects of the earlier Campbell plot, and to Meghan's Edwardston experiences.

Hibernia's deposed King, James IV, continues to influence events from behind the scenes as various of his allies and enemies try to determine what became of him after the 1941 deposition. Scholars, students, soldiers, loyalists, rebels, and athletes--among them Christians, agnostics, and hardened sinners--populate the history of his interregnum. He and Clan MacCarthy's leaders continue pursuing incompatible visions of Tara's throne--a symbol of justice and honour for James, of racist oppression for his opponents.