Cut to the Chase:
Ellen (Sharon Stone) kills Herod (Gene Hackman) and rides away, albeit wounded, leaving Cort (Russell Crowe) as the new Marshall of the town of Redemption.
Herod kills the Kid (Leonardo DiCaprio), who wanted his respect because he thought Herod was his father (but Herod says he wasn't). Herod gets a fleshwound on the neck.
Ellen has to fight Cort before she can fight Herod, but, although both want to kill Herod, neither wants the other dead.
During the quick-draw duel, both Ellen and Cort hesitate before drawing, until Herod announces that they will both be shot by his men if they haven't drawn before he finishes counting down from ten. Ellen and Cort draw, and it looks like Cort has killed Ellen. She's bleeding from a chest wound, and the town doctor, who knew her from birth, keeps the corpse-robbers away from her.
Cort goes up to Herod to kill him then, but Herod says it has to be the next day, according to the rules of the quick-draw contest, and tells Cort to pick the time. Cort chooses dawn. (Although, technically, the time will be 6 o'clock, since the ringing of the clocktower is the signal to draw guns.)
During the night, one of Herod's men, who is guarding Cort, wounds Cort's right hand. At dawn, Herod finds out and angrily dismisses the man, giving him 20 seconds to get out of town. While the man is running away, Herod shoots him in the back with a rifle.
Now Cort and Herod are facing each other (Herod has offered to draw with his left hand, to even the odds). But when the clocktower strikes 6, it explodes. And so do several other buildings in town, including Herod's house.
Ellen walks out of the smoke and fire, very much alive. The blood from before was actually ink from the blind shoe-shine boy, and she used the Kid's dynamite to blow up Herod's assets. Cort shoots Herod's men.
Herod and Ellen face each other down, and he tells her she's not fast enough for him. She says that today she is, and throws a marshall's badge at him. In flashback, it's revealed that Ellen's father (Gary Sinise) used to be the town marshall, until Herod and his men arrived and stringed him up to hang him. Herod gave a very young Ellen the chance to try to free her father by shooting the rope, but Ellen missed and killed her own father accidentally. This is why she wants revenge. (Earlier in the movie, Ellen successfully shot the rope to which Cort had been hung in the saloon, saving his life at the last second.)
Ellen and Herod draw and shoot. Herod wounds Ellen, but Ellen puts a hole through Herod's chest. Herod goes to shoot again, but Ellen is faster, and shoots him in the eye, and he falls down dead.
Ellen picks up her father's badge and gives it to Cort. She says that the law is back in town, and rides away, cheered by the townspeople.