The serpent is chasing the twin brothers who are trying to get their father back from the underworld.

Nothing extraterrestrial about it, except maybe for the headsets, but who knows?

I'd love it to be extraterrestrials, however, if they were extraterrestrials, they certainly destroyed themselves several hundred years ago. It is often the problem with civilization.

Alot of civilisations unless they can pass a certain point in their critical mass and become a mature species, will die out from mass extinction around 300 years after the invention of the radio.