As the comet fills the sky over Britain and rumours of war coming from across the channel spread two young men accompany a lecherous bishop north to the ruins of the ancient Hadrian's Wall to search for a man known only as 'the last Roman' and the mysterious prophecy he keeps - the prophecy of Isolde. It is a prophecy that tells of an invasion by a North man and an empire that will last thousands of years, an empire of the Aryans. Stephen Baxter's new series is full of page-turning action, intriguing mystery and awe-inspiring scientific speculation. Full of evocative historical detail and characters who jump of the page this is history lived by people who's future is not yet locked as our past.