In 140 AD, twenty years following the unexplained disappearance of the complete Ninth Legion from the hills of Scotland, young centurion Marcus Aquila (Tatum) takes place from Rome to address the mystery and restore the standing of his father, the commander of the Ninth. Accompanied only by his British slave Esca (Bell), Marcus lays out across Hadrian's Wall in to the uncharted highlands of Caledonia - to face its barbarous tribes, create peace with his dad's memory, and regain the lost legion's golden emblem, the Eagle of the Ninth.