15 Most Terrifying Movie Aliens Of All Time

It's hard to think about War of The Worlds without getting flashes of those giant destructive Tripods, but it's the creatures behind those war machines that are the most horrifying thing about the 2005 film.

Relatively large creatures, it's clear that their design was inspired by the Tripods as they move around on three large legs/arms - all of which also have three long fingers. Their most intimidating aspect, however, are their large heads which houses sinister faces with two black marble-like eyes.

In spite of the fact that they're clearly alien, the most haunting thing about these creatures are the vague similarities they bare to humankind; something that is reinforced throughout the film by their child-like curiosity and high level of intelligence.

Though the aliens originate from Mars in H.G. Wells' original novel, Steven Spielberg made the creative decision for his film versions to come from an unknown planet instead, simply because humanity had learned so much more about Mars. And as we tend to fear what we do not know, that made them that much scarier.