Michael B. Jordan stars as Adonis Johnson, the illegitimate son of former world heavyweight champion boxer Apollo Creed, who died in the ring before he was born, and a woman Creed had an affair with who died while Adonis was a young boy. Apollo's widow Mary Anne pulls Adonis out of his hard-knock life foster care and juvenile hall to adopt him as her own son, raising Adonis to be a fine young man with a bright future in business. However, it seems Adonis is his father's son after all, opting to drop out of white-collar life for a chance to prove himself in the ring as a self-taught, up-and-coming pugilist, undefeated as an amateur boxer in Mexico before deciding to head out to Philadelphia to seek out the training of Rocky Balboa, current South Philly restaurateur who was once the boxer who ended Apollo's reign in the ring before they became good friends later in life. Rocky's initially reluctant, but soon capitulates to the earnest young man's demands. Despite wanting to make it on his own terms as Adonis Johnson (his mother's maiden name), soon word gets out that he's Apollo Creed's son, which opens a huge door of opportunity when the reigning light heavyweight champion from England, "Pretty" Ricky Conlan, wants one big marquee match-up to give him enough money to survive before he goes off to prison. Long-shot odds for Apollo ratchet up to next to impossible when Rocky is diagnosed with a serious illness that threatens to take the former champ down for the count for good.