In 1870, reformed outlaw Jess Wade is
tricked into believing that his former girl friend Tracy urgently
wants to see him. Riding into a small Mexican border town,
Jess is captured by the band of outlaws, led by Vince and his
deranged brother Billy Roy, that he had abandoned a year before in
order to lead an honest life.
Jess is taken to the gang's mountain
hideout and shown the legendary Victory Gun--the cannon that fired
the last shot against Maximilian and won freedom for Mexico--as well
as a counterfeit poster proclaiming that he is wanted dead or alive
by both Mexico and the United States for the theft of the cannon.
Jess manages to get away, and he seeks safety in the village of Rio
Seco, where Tracy operates the local saloon and Sheriff Ramsey is a
trusted friend.
Billy Roy appears on the scene and
seriously wounds the sheriff in a gunfight. After subduing
Billy Roy and dragging him off to jail, Jess arms the townspeople
for a possible attack by Vince's gang. But Vince eliminates
outside reinforcements by ambushing a platoon of Mexican cavalry,
and he threatens to turn the Victory Gun on Rio Seco unless Billy
Roy is freed. To back up his warning, Vince fires several
shots which topple the church steeple and kill Sheriff Ramsey.
Jess takes Billy Roy up to the mountain
hideout when the panic-stricken citizens insist that the prisoner be
released. During the fighting that ensues, several gang
members are slain, and Billy Roy is killed when the wagon holding
the cannon breaks loose and crushes him. Jess takes the
defeated prisoner and drives the cannon wagon back into Rio Seco.
Although the grateful townspeople ask Jess to remain on as sheriff,
he declines, stating that he must take the cannon and Vince back to
Mexico. Before riding out of town, however, Jess promises
Tracy that he will send for her.