An ex-Union gunfighter attempts to protect his plague-ridden hometown from being overridden by his racist half-brothers and a Confederate tyrant.

Keoma returns to his border hometown after service in the Civil War and finds it under the control of Caldwell, an ex-Confederate raider, and his vicious gang of thugs. To make matters worse, Keoma's three half-brothers have joined forces with Caldwell, and make it painfully clear that his return is an unwelcome one. Determined to break Caldwell and his brothers' grip on the town, Keoma partners with his father's former ranch hand to exact violent revenge.—Ørnås

After the American Civil War, Keoma returns to his homeland and rescues a beautiful pregnant woman accused of having plague, Lisa, from a gang leaded by the landlord Caldwell. Later he meets his former slave servant and friend George, now a drunk free man, and his father, William Shannon, and he is informed that the town is under siege of Caldwell's men, without supplies of medicine or food and justice, with the dweller dying of plague and starvation and sick people is being isolated in an old mine. Further, his three dangerous half-brothers have joined Caldwell's force. Keoma decides to help Lisa and the dwellers to retrieve their freedom and dignity, and he finds how despicable the inhabitants are.—Claudio Carvalho, Rio de Janeiro, Brazil