Pompeii (2014) on Netflix

In 79 A.D., a Celtic tribe of horsemen is slaughtered by the Roman Senator Corvus, his right-hand man Proculus and their army. The boy Milo is the only survivor that is captured later and sold as slave. Seventeen years later, the slave Milo turns into an invincible gladiator in a province and is brought to Pompeii to participate in the games in the arena. While walking to Pompeii, the noble Cassia and her chaperone Ariadne cross with the path of the slaves and Cassia is fascinated by Milo. He shares the cell of Atticus, who is near to get his freedom depending on winning his last fight. Meanwhile Cassia meets her parents Severus and Aurelia and learns that she has been betrothed to the corrupt Senator Corvus who is pressing her parents to marry her. During the games, the Mount Vesuvius erupts and Milos and his friend Atticus succeed to escape from the arena. But Milo wants to save his beloved Cassia in the middle of the chaos and the Romans.