Late in 1974, somebody (possibly still drunk from our long, national, Watergate bender) thought Harlan Ellison's post-apocalytic, science-fiction/horror/black comedy novella, "A Boy and His Dog", would make a terrific movie. It hit America's theaters in November, 1975 and then promptly disappeared into America's sketchier art-houses and science fiction convention all-night movie marathons.
It gave a young Don Johnson's career a big boost, keeps the novella's punchline intact, but adds final line of dialogue which Harlan Ellison described as a "moronic, hateful chauvinist last line, which I despise."