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From 'E.T.' to 'Arrival,' these are the best alien movies of all timeby Circa News
Hollywood#Slideshow
These are the best alien movies of all time.
How many have you seen?

Do you think that we're all alone? Or do you believe that other life forms exist somewhere out there? You have to admit that the possibility is intriguing. There's just so much that we don't know. What would aliens actually look like? Would they be friendly or would they attack?

There are tons of movies that have explored this topic over the years, each presenting a unique scenario of what could happen if aliens reached our planet. Here's our definitive list of the all-time best movies about aliens, ranging all the way from "E.T." to "Arrival."