Robert Duvall has appeared in some landmark dramas -- Apocalypse Now , The Godfather , To Kill a Mockingbird -- but he's made his greatest mark on the Western. With credits ranging from True Grit (with John Wayne) to AMC's own Broken Trail , he's earned a reputation as Hollywood's Last Great Cowboy. Don't believe it? Take a look for yourself with Open Range tonight at 8PM ( for a full schedule this month, click here ) or check out this gallery of Duvall in his most memorable Western roles. ...