Sexmission (1984)

Two scientists are chosen as guinea pigs for a time experiment: they are placed in hibernation and should be brought back to life after three years. In the meantime, however, the World War III breaks out and life have been wiped out of the surface of the Earth. When they wake up, it turns out that not only 50 years have passed but also that they are the only living specimens of the male sex in a new, underground society composed exclusively of women.