Aliens have been visiting earth since prehistoric times, and in fact even Humanity may have originated in the stars, and were created through bio-engineering by other races to inhabit this planet, so the theory goes on Ancient Aliens. You may know it from the Giorgio Tsoukaloz meme (the guy with the mad hair who always says everything is related to Aliens) :
Follow the link below to watch:
I’ve been looking around for ages trying to find episodes of this show to watch online for free. It’s tough to find or even to buy this show but I’ve located it on Blaze TV there, and there are many episodes up there to watch.