The film follows Maximus Decimus Meridius (Russell Crowe), a loyal general in the Roman army who is betrayed by the corrupt emperor Commodus (Joaquin Phoenix). As the film begins, Maximus is a revered military leader who leads Rome to victory in a crucial battle. However, when Emperor Marcus Aurelius (Richard Harris) dies, Commodus seizes the throne and orders the execution of Maximus and his family.

Maximus narrowly escapes death but is captured and sold into slavery. He becomes a gladiator and rises through the ranks of the arena with his remarkable combat skills and leadership. His ultimate goal is to seek revenge against Commodus and restore justice to Rome.

As Maximus gains fame and respect as a gladiator, he attracts the attention of the Roman populace and becomes a symbol of hope. He uses his growing influence to challenge Commodus and expose the corruption of the new regime.