critics of the film have also pointed out similarities between this and herman melville's classic novel "moby-dick". many of the characters are similar to those from that book, with dundee as captain ahab, tyreen as starbuck, ryan as ishmael, and other minor characters, with sierra charriba and his apache tribe substituting for the whale, as is the general plot line (an obsessive idealist drives himself to destruction, disregarding the effects on others). these references to "moby-dick" were likely intentional on the part of the screenwriters. some have also pointed out similarities of the plot to the vietnam war, which are highly unlikely to have been intentional, as the war had not significantly escalated at the time of the film's production.