The third and final entry in the BACK TO THE FUTURE Trilogy sees Marty and Doc in the Old West of Hill Valley in 1885, where Marty must save Doc from getting gunned down by an ancestor of Biff Tannen.  It's a softer, and more romantic effort, as Doc finds love with the charming schoolteacher, Clara Clayton, who is also supposed to meet her maker, unless Marty can figure out a way to save them both without messing things up for the future!