Rocky Balboa (Sylvester Stallone), a name that once sent adrenaline rushing through the veins of fans, has gradually been forgotten with the passage of time. Since the death of his wife Adrian from cancer, the reticent Rocky has become even more silent. His daily routine consists of nothing more than visiting the pet store, taking care of his good friend and brother-in-law Paulie (Burt Young), cooking for himself, and sitting alone at his wife's gravesite as a form of solace. Even his son Robert has grown increasingly distant, unwilling to live in the shadow of his legendary father.
The current headline in boxing circles is Mason Dixon (Antonio Tarver), the new heavyweight champion whose powerful straight punches, quick footwork, and robust physique have quickly made him the new darling of boxing enthusiasts. However, during a computer simulation matchup hosted by the globally popular ESPN channel, Rocky shockingly defeats Mason after an intense battle! Though the computer match is merely theoretical, under Paulie’s encouragement, Rocky’s passion for boxing and fighting spirit are reignited...