FUTURE SHOCK: Six years before “Star Wars,” a 27-year-old George Lucas offered a vastly more austere (and less popular) variety of science fiction in his feature debut “THX 1138,” which he expanded from his student short. This Orwellian, Kubrick-influenced tale, produced by Francis Ford Coppola, casts Robert Duvall as a member of a computer-controlled future society where sex is banned and everyone shaves their heads and wears shapeless outfits. After Duvall’s roommate (Maggie McOmie) introduces him to sex, he lands in prison, and breaks out with the help of Donald Pleasance. A new, computer-tweaked “director’s edition” begins an open-ended run today at the Empire at 42nd Street and Eighth Avenue, in advance of its debut on DVD (via Warner Home Video) on Tuesday.