Old SF movie with bald people, a radiation and mysterious cave

[wositelec]

I am looking for SF movie (it is movie between 50s and 70's). My friend remembers only scene, in which immortal people are after radiation. They are probably gray or silver color, they are bald completely and hidden in caves. They are reached by people from the top of the planet who have become immune to radiation or survived it. A scene similar to that of Planet of the Apes, where there they meet these old people in the underground.The silver people were similar to these from "The Creation of the Humanoids" (1962).

It isn't "Time Machine" (1960), although Morlocks are some similar, but they aren't bald. I think that it could be very low-budget, because I asked in different message boards, but no effect.

[LilCerberus]

It could be The Time Travelers (1964) which has a similar plotline...

However, the silver skinned aliens sounds like an Italian series of low budget films by Alfonso Brescia, which also have similar subplots....

Cosmos: War of the Planets (1977)
Battle of the Stars (1978)
The War of the Robots (1978)
Star Odyssey (1979)
Beast in Space (1980)

[wositelec]

Thank you again. I will check these tropes. Perhaps it will be "Time Travelers", but I have to speak with my friend.