AD 400. Rome and its Empire are failing... Veteran cavalry commander Marcus Flavius Victor sets out with his regiment to make what may be his final tour of the forts along Hadrian's Wall.Through a combination of military prowess, brutality and bribery, Marcus has spent twenty years keeping the savage Picts at bay. Feared by his enemies and hated by his superiors, his strength of will is the only thing that has held the disgruntled, poorly paid garrisons of the Wall in place as the failing Roman Empire's grip on Britannia weakened.Yet as this tour of the wall progresses, it becomes increasingly clear that this is more than a routine inspection. Why is Marcus stripping the defences of cavalry to strengthen his own force? Is he negotiating with the Picts - or conspiring with them? And who is the mysterious figure who follows Marcus' every move and yet hides in the shadows? Segeduno, Cilurno, Brocolitia, Vindolanda: each fort holds memories and friendships, hides rivals, or conceals enemies. But what exactly is Marcus Flavius Victor's ultimate objective? It would appear he is willing to risk bloody civil war in a bid to seize Britannia for himself? Or is he raising an army to save the province from the darkness that waits on the other side of the Wall?