There was a slew of interesting, thought-provoking scifi made in the lull between 2001:A Space Odyssey and the juggernaut of movie scifi that was Star Wars, that for many years made movie sci-fi==movie sci-fantasy. Stuff like THX 1138, Omega Man, Soylent Green, The Last Warrior, Silent Running, Dark Star. Logan’s Run comes near the bottom of the pile. It’s got a wonky script and the actors are not directed well, but even coming near the bottom, it’s still worth a watch. The beautiful Jennifer Agutter disrobes a lot (and is easy on the eye when clothed too), and Peter Ustinov’s turn as a cranky old guy spouting T.S.Eliot is fun, as is a mad robot obsessed with freezing people.

The world-building is also quite interesting (if a little star trekky), and I think this one would be a good candidate for a remake.