Following the American Civil War, veteran Benjamin Trane (Gary Cooper) and gunslinger Joe Erin (Burt Lancaster) are just two of many men who head to Mexico as mercenaries. When Emperor Maximillian (George Macready) recruits their services, they reluctantly work together, since the price is right. Trane and Erin are to escort Countess Marie Duvarre (Denise Darcel) to Vera Cruz -- but when they find a wealth of gold hidden in the stagecoach, the original plan no longer applies.