Marcus Flavius Aquila is the central character of The Eagle. He is a determined and brilliant soldier but his reputation is tarnished by stories that his father, Flavius Aquila, had taken Rome’s 5,000-strong First Cohort of the Ninth Legion, into Caledonia, carrying their treasured golden emblem, the Eagle of the Ninth, only to disappear forever.

Having been given command of a small fortlet in the southwest, Marcus bravely leads his troops during a siege. Marcus is commended by Rome for his bravery, but is discharged from the army because of his severe wounds. Taking up residence with his Uncle (played by Donald Sutherland) to aid his recovery, Marcus hears rumours of the Eagle of the Ninth being sighted once again in Caledonia and is galvanised into action. Accompanied by his slave companion, Esca, he vows to travel beyond the northern frontier of the Roman Empire and retrieve the Eagle, thereby restoring hope and honour to the Roman Empire as well as his family’s name.