El Dorado is a 1966 American Western film directed and produced by Howard Hawks and starring John Wayne and Robert Mitchum. Written by Leigh Brackett and loosely based on the novel The Stars in Their Courses by Harry Brown, the film is about a gunfighter who comes to the aid of an old friend who is a drunken sheriff struggling to defend a rancher and his family against another rancher trying to steal their water. From Wikipedia
