A group of Venusian mermaids (Mamie Van Doren and assorted scantily clad blondes) wearing seashell bras and hiphuggers, interact telepathically with cosmonauts from a relatively expensive-looking Russian science fiction film.
As the cosmonauts encounter man-eating plants and various dinosaurs, the hippie mermaids watch and sing, swim, spy, eat raw fish while treading water, worship a pterodactyl, and generally lounge around and wait to see what happens.
When the cosmonauts shoot down their pterodactyl god (in self-defence), the ladies take action, get really mad and create volcanos and floods by chanting like witches.
This strange film came about because Roger Corman acquired the rights to several 1960s Russian science fiction films and tasked young Peter Bogdanovich with dubbing the Soviet film Planeta Bur (1962) into English and adding Mamie Van Doren and a cadre of her fellow blonde sea nymphs to ramp up the sex appeal.
Bogdanovich and production coordinator Polly Platt merged new and old footage superbly, such as when a Hollywood-made rubber pterodactyl corpse washes up in the surf for the girls to find, pray over and send back to the sea after a (far more elaborate) Russian counterpart is shot down by the cosmonauts.
Some additional special effects shots from another Soviet production, The Sky Calls (1959), were also added.
A giant man-eating plant, the attack of the man-sized Allosauruses, and a passing Brontosaurus are just icing on the cake.
Bogdanovich also provided the hipster narration (as the younger, romantically inclined cosmonaut).
Mamie Van Doren
Capt. Alfred Kern
Georgiy Teykh (as James David)
Women of Venus
Astronaut Howard Sherman
Yuriy Sarantsev (as Ralph Phillips)
Astronaut Hans Walters
Georgi Zhzhyonov (as Murray Gerard)
Astronaut Andre Freneau
Gennadi Vernov (as Aldo Romani)
Cmdr. William ‘Billy’ Lockhart
Vladimir Yemelyanov (as Roberto Martelli)
Peter Bogdanovich (as Derek Thomas)