Dr. Owen Whitfield is the elderly Oxford professor of history who first appeared in Michael O'Brien's novel The Father's Tale. In the events of The Sabbatical, which occur sometime later, Dr. Whitfield is looking forward to a sabbatical year of peace and quiet, gardening in his backyard, and tinkering with what he calls his latest "unpublishable book".

As the year begins, he is drawn by a series of seeming coincidences into involvement with a group of characters from across Europe, including a family that has been the target of assassination attempts by unknown powers. During his journey to Romania, the situation in which he finds himself becomes more sinister than it first seemed.

The story deals with the tension between fatalism and the providential understanding of history, with the courage and love that are necessary for navigating through a confusion of signs, and with the triumph of faith and reason over the forces of destruction.