This was a banner year for sci-fi movies. Several big hits would become sci-fi landmarks like Omega Man and A Clockwork Orange. Dystopia was also becoming a recurring theme. Between the hits, there were plenty of low-budget B films to keep the average down. Below are the sci-fi films of 1971 in fairly chronological order:
City Beneath The Sea -- A Irwin Allen pilot. An underwater city houses America's gold. It's being robbed when a giant meteor threatens.
A Clockwork Orange -- Stanley Kubrik's dystopic tale of gang violence and brutal behavior modification.
THX 1138 -- George Lucas' dystopic tale of modern life as human automatons, where love is illegal.
The Andromeda Strain -- Big budget film about a deadly space germ brought to earth for weapons research. It escapes the lab.
When Dinosaurs Ruled The Earth -- Yet another cave man (and scantily clad cave woman) film. Loose remake of One Million Years B.C..
The Fear Chamber -- One of four mexican-american cheapie films that were Boris Karloff's last. A rock creature "feeds" on fear - especially that of young women.
Alien Terror -- Another of Karloff's last. His beam weapon research attracts the attention of aliens who want to stop his project.
Escape From the Planet of the Apes -- Cornelius and Zira travel back in time to 1970. They become hunted as a menace to mankind.
The Omega Man -- Epic (second) remake of "I Am Legend" starring Charlton Heston as the last man on earth battling the zombie-like "brothers".
Glen and Randa -- An obscure indie post-apocalyptic tale. Two teens search for a mythic Metropolis amid the ruins of civilization.
The Big Mess -- German indie film: Der Grosser Verhau. A rogue space merchant runs afoul of galactic government. Chaotically told.
Quest for Love -- A British physicist accidentally travels to a parallel 1970 and falls in love with his alternate self's neglected wife.
Yog: Monster From Space -- Another Toho kaiju. A sparkly amoeba from space comes and makes several creatures into giants so it can conquer earth.
The Resurrection of Zachary Wheeler -- Senator Wheeler is mortally injured in a car crash, but a shadowy organization saves him in exchange for political favors.
The Incredible 2-Headed Transplant -- A misguided doctor transplants the head of a psychopath onto the body of a big dim man. He/they escape and mayhem ensues.