The story is set partly in the 13th century and partly in the modern day, and is based on a Herefordshire legend, which appears to have been corroborated by historical circumstantial evidence.
Legend says that about eight o'clock each evening, a phantom woman in a small boat appears, sailing along the River Wye. She always goes ashore at the same place, where she would weep and wail hysterically. She would then return to her boat and sail back towards Hereford.
In 1999, Aldith and William Abridge are about to inspect their legacy of a large country estate near Ross-on-Wye in Herefordshire, built over the site of a mediaeval monastery. Aldith hesitates to go into the house as she receives painful electrical shocks from a bracelet; however, gathering her courage, she steps across the threshold and vanishes. Through the catalyst of the bracelet, bought from a local antique dealer, the curse of the goddess of retributive justice, Nemesis, is triggered and Aldith is drawn back through a portal to the 13th century.
Reincarnated as a local village maiden, Aldith finds herself in the monastery of Aconbury. Discovered by two monks, she stands accused of having seduced and then murdered a monk. Despite her protestations of innocence, she is locked in a cell to await her judgement. Meanwhile, the monastery is set fire to by the infamous Marcher Baron, William de Braose, and Aldith dies in the flames.
Back in the present day, William finds that his wife has vanished without trace.
The story then tracks his increasingly desperate attempts to find his wife. Yet despite police investigations and using the services of a world-renowned Psychometrist, no trace of William's wife can be found. Researching mediaeval texts held at the famed Chained Library of Hereford Cathedral still does not throw up any clues.