In "Desert", Alias (as Indian Guide) leads Billy to the Mexican Sweetheart's hide-out. Billy has no thought for anyone but himself and the Sweetheart leaves. The Indian Guide returns with Garrett, and, when Billy lights a cigarette in the darkness, Garret kills him ("Billy's Death"). Mexican women mourn Billy's death in "Pietà". The ballet ends with Garret leading pioneers in "Closing March".