In the grandeur of the Roman Empire, Centurion Marcus Antonius Maecilius is a man of honour and valour. Yet, fate deals him a cruel hand when he is falsely accused of cowardice and sentenced to serve as an oarsman on a bireme, a slave to the rhythm of the waves and the lash of the overseer.

Broken and embittered, he resigns himself to the monotonous toil of the galley—until the day a mysterious group of five men board his ship in Hispana with orders for the captain to take them to Belgica in the northern seas.

Unbeknownst to Marcus, these elite operatives, selected from the best of the exploratores, are on a clandestine mission deep into the heart of Germania, and when the ship is forced to engage a Gallic pirate ship, his bravery shines through, catching the eye of Seneca, the man in charge of the exploratores.

Offered a chance to join their elite ranks, Marcus must make a decision that will change his life forever. Does he stay and live out his sentence before seeking justice, or does he join these secretive men, who, by their own admission, doubt they will come back from their mission alive?

Set against the backdrop of the ancient world's most formidable empire, Dark Eagle is a dramatization of the secretive world of those who fought for Rome in the shadows. Unknown to most, their battlefields were often behind enemy lines, clandestine missions to seek information and, where necessary, dealing death without hesitation.

In today’s world they would be called special forces but back then, they were known as the Exploratores.