During the Franco-Mexican War, ex-Confederate soldier Ben Trane (Cooper) travels to Mexico seeking a job as a mercenary. There, he meets Joe Erin (Lancaster), a lethal gunslinger and leader of a gang, and they all are recruited by the French to escort the Countess Duvarre (Denise Darcel) to the seaport city of Veracruz. During a river crossing, Trane and Erin notice that the stagecoach in which the countess is traveling is extremely heavy. Erin later discovers that the stagecoach contains six cases of gold coins. The countess informs them that it is worth $3 million which is being transported to pay for troops for Emperor Maximilian's French army. Trane and Erin form an uneasy alliance to steal and split the gold.
Unfortunately for their plans, the man who hired them, the Marquis de Labordere (Cesar Romero), discovers their scheme, and after a group of Juaristas and the rest of Erin's group also suspect that there is more to the expedition, the different groups, including Juarista secret agent Nina (Sara Montiel), conspire to steal the gold for their own purposes. Alliances are formed, quickly dissolved and others are formed.
Although relatively obscure today, Vera Cruz was a major box office hit in its time, making $11 million on a $1.6 million budget. The movie was a major influence on later Westerns which used its storyline of American outlaws or mercenaries traveling to Mexico: The Magnificent Seven, The Professionals and Sergio Leone's three Dollars films all owe a heavy stylistic debt to Aldrich, while Sam Peckinpah's Major Dundee and The Wild Bunch both feature several overt Shout Outs.
This film provides examples of:
- America Saves the Day: In this film set in a war between France and Mexico, while the U.S. Army doesn't appear,note it's the conflict between two Americans that becomes the climatic showdown.
- Artistic License Military: All the French soldiers are depicted in uniforms and helmets that were worn on parades and formal ceremonies, not when deployed out on the field. The only scene in the movie where such ceremonial uniforms are justified is the protagonists' arrival at Chapultepec Castle in Mexico City and the subsequent ball.
- Ax-Crazy: Erin shows signs of this throughout the movie, for example when he swipes Little-Bit's loaded revolver from him and threatens him with it while they're inside the monastery. This ultimately culminates in him gunning down one of his henchmen for no reason in the finale.
- Bad Boss: Overall, Erin was a dick to his men, from not letting them in from the beginning about the gold, to gunning down one of his henchmen for no reason in the finale.
- Everyone Has Standards: Ben Trane may be an ex-Confederate soldier who went to Mexico to work as a mercenary, but he gets gradually fed up with Erin's violent antics. After Erin guns down one of his henchmen for no reason in the finale, this finally sends Trane over the edge.
- Faux Affably Evil: Erin tries to put on an affable façade, specially with Trane, but by the end of the film it becomes clear that it's just for show and that he truly is a thug.
- For the Evulz: In the finale, Erin guns down one of his henchmen for no reason.
- Gory Discretion Shot: We only get to see Nina's reaction as the soldiers kill a Juarista off-screen.
- I Control My Minions Through...: Fear and power, by Erin. It's increasingly clear as the movie progresses that he controls his men as much through their fear of him and his unpredictable behavior as he does through his leadership skills.
- Mighty Whitey: Trane eventually decides to become the all-powerful champion of Juarez's cause.
- The Mole: Nina, a Juarista pretending to be a wandering pickpocket. Trane cottons on to her soon enough, though.
- Slobs vs. Snobs: The scruffy guerrilla army of the Juaristas vs the impeccably dressed troops of the Imperial Mexican Army and their French contingent.
- South of the Border: The film manages to pack just about every feature of this trope in the Second Mexican Empire.
- Spicy Latina: Nina is a sultry Latin woman with a fierce temper and a rough background, what with being in the Franco-Mexican War and all.
- Teeth-Clenched Teamwork:
- Trane and Erin form an uneasy alliance through the film, especially from Trane's side, due to him objecting to Erin's methods.
- The other groups looking for the gold form quite perishable alliances.
- Would Hurt a Child: At one point, Erin threatens to murder some child hostages.