One of the best films by often-underrated director Robert Aldrich, this stark, brutal Western is also an effective allegory of America's involvement in the Vietnam War.
Set in Arizona during the late 1880s, the film begins with experienced scout McIntosh (Burt Lancaster) and idealistic U.S. Cavalry Lieutenant DeBuin (Bruce Davison) setting out to catch a group of Apache renegades lead by their chieftain, Ulzana (Joaquin Martinez). The story focuses on the opposing views of the two men regarding Ulzana.
McIntosh is cold and cynical while DeBuin is morally outraged by supposed Apache atrocities. The film, sharply written by Alan Sharp, poses a set of complex questions about the nature of heroism, racism, and American imperialism, while avoiding moralizing or oversimplification of the issues.
Aldrich and Burt Lancaster, who made four films together over the course of their long careers (including this one), later collaborated on the excellent political thriller Twilight's Last Gleaming.