The Professionals (1966)

Wealthy Texas oilman Joe Grant hires four professional soldiers to retrieve his wife Maria from a Mexican revolutionary and bandit by the name of Jesus Raza who is demanding $100,000 for her return. He promises the four men $10,000 for what amount to 9 nine days work. Two of the men, Rico Fardan and Bill Dolworth, know Raza from their own days fighting with Pancho Villa during the Mexican revolutionary war. They make their way to Raza's encampment, with a battle or two along the way, and in the end have little trouble getting hold of Maria Grant. What they learn however leads them to question just who the kidnappers are and how they should deal with their employer.

IMDb: https://www.imdb.com/title/tt0060862