Brett McBain and his family are preparing to welcome Brett's wife Jill (Claudia Cardinale) into town when all of a sudden they are killed. A mysterious lone stranger (Charles Bronson) arrives and is looking for the man who killed Jill's family: Frank (Henry Fonda), a merciless gunfighter/assassin, who works for Mr. Morton and his railroad company. A bandit, Cheyenne (Jason Robards), joins forces with this stranger against Frank and at the same time they aid Jill. Why is the stranger after Frank?? What's the connection between them?