[The Nung River is fictional - and represents he Mekong River.] Willard is told to be a military assassin and "terminate he Colonel's command." According to Corman, "he's out here operating without any decent restraint, totally beyond the pale of any acceptable human conduct - and he is still in the field commanding troops." The conversation turns icy when Dr.Floyd is asked about the "odd things" that are happening at his destination, the American moon-base on the moon crater of Clavius, and why it has been out of phone communication for 10 days.Villainous arch-nemesis and career criminal Lex Luthor (Kevin Spacey) was first introduced (off-screen) speaking to frail and wealthy widow Gertrude Vanderworth (Noel Neill, who portrayed Lois Lane in 78 episodes of the TV showAdventures of Supermanfrom 1953-1958).Two main characters were introduced in the interior of one of the train's passenger cars:Letty Mason (Lillian Gish), a dainty, sweet young lady from Virginia, with a frilly lace shoulder piece and bonnetWirt Roddy (Montagu Love) - sitting behind Letty and gazing at her; a western cattle rancher wearing bootsHe approached Letty's seat, paused to brush sand from his sleeve (a repetitive gesture copied by many of the male characters), and then continued on.A premature explosion caused by the Alien's sudden appearance resulted in accidental deaths, although the fire was extinguished by sprinklers.