Don Johnson stars as a member of a United States Cavalry detachment refusing to slaughter its horses after being ordered to do so by General Douglas MacArthur.

World War I veterans are protesting and rallying in Washington, D.C., demanding immediate cash redemption of bonus certificates that were due to be paid in 1945.

First Sergeant or "Top" John Libbey (Don Johnson) and three fellow soldiers refuse to draw their swords because the demonstrators are men with whom they served during the war.

During his interview with retiring Colonel Stuart (Rod Steiger), it is revealed that he has been assigned to this post because he attacked another soldier for hurting his horse.

Lieutenant Buxton meets Sergeants Libbey, Quinlain (Neil Melville), Mulcahey (John Dennis Johnston), and Shattuck (Robert Coleby), who together manage the herd of remounts.

While watching the first 100 helpless horses being shot in a mass grave, Lieutenant Buxton decides to end the massacre and drive the remaining herd to safety.

The original plan is to take the horses to the Indian Reservation in Montana, where they will be safe, but because of Hardesty's Armored Division they are forced to go north to Canada.

In his 1992 painting Save the Wild Horses, created for a Smithsonian fundraiser, Stockton Master Artist Jack Feldman depicted the mustangs, rounded up, their eyes glowing red, illuminated by spotlights, in a nighttime mass slaughter.