Yorkshire in 51AD was the tribal heartland of the Brigantes, the largest Celtic confederation in Britain and a huge stumbling-block in Roman plans for the conquest of these isles.
Cartimandua, Queen of the Brigantes, is thought to have had at her disposal a huge force of arms for the time - 15,000 or more of the finest warriors in Europe. But her real power lay elsewhere.
In her hands was entrusted the spiritual future of Britain. She was the last of a royal line stretching back to humanity's earliest dawn.
From this line Cartimandua inherited a pact with the Rook Goddess Brigid, patron spirit of Britain - to preserve the worship of the old gods of river and lake, mountain and standing stone, tree, bird and beast, the stars and planets.
As the symbol of this pact a golden Torc, or necklet, was passed from generation to generation down the royal line. The power of two worlds, the spiritual and material, met seamlessly in this Torc. That power was so strong it could warp leylines, call deities into being . . . and kill at a touch.
In the southern kingdoms Prince Caradoc, known to the Romans as Caratacus, had rallied the Celts in running battles through England and Wales. From the first invasion in 43AD he had represented the might and will of the British to resist the power of Rome.
Yet his strength was as nothing against the skill and brutality of the legions. He turned to the Brigantes in one final bid to throw Rome back into the sea. He wished Cartimandua to use her warriors – but he wanted her to invoke the power of the Goddess too.
Instead, Cartimandua attempted to parley with Rome, succeeding only in betraying the Goddess, alienating her husband Venute and splitting the Brigantian tribes asunder.
The pact was broken. The Torc was wrested from the queen and Brigid laid on it a sorrowful curse:
'As long as the stain of Rome soaks Pretan's soil, my power shall sleep, and with it shall sleep the souls of my people.'
Then she cast the Torc into the ground, and set her familiar, a wise rook called Hroc, and all his kin, to guard it where it lay, for eternity if need be.
So Rome's military juggernaut crushed the spirit of the Celts and the magic of old Pretan. Under its uneasy mantle of Christianity the island and her gods slept for nearly 2,000 years, their markers the standing stones and barrows, their heritage a host of half-remembered festivals, customs and superstitions.
Now, thanks to a devious builder's plan to develop the site where the Torc is buried, a history teacher's obsession with stopping him, and the guardian rooks' dogged determination not to let the Torc fall into the wrong hands, Brigid's lethal secret is about to burst on a post-Christian world.
It is time for an awakening.