Train Robbers (1973)

Lane (John Wayne) is a corruptible gunman and cowboy who is hired one day by a young widow (Ann Margret) to search for and recover the treasure that belonged to her recently deceased husband. The woman wishes to do so as the treasure was stolen by her outlaw husband during a daring train heist a short time ago, and she will return it to the authorities and move to another land as to start a new. Lane and some of his befriended riders set out to find the stolen gold, but they are not alone in its quest as other outlaws are on the trail as well. A showdown between the two is forthcoming and will have fatal consequences.