10 Great Sci-Fi Movies Where The Aliens Walk Among Us

8. Cocoon

From sucking the life force out of the entire human race to rejuvenating the elderly with a swimming pool charged with a powerful "life force", Cocoon shows that sometimes the aliens really do come in peace. Cocoon plays on the idea of the ancient city of Atlantis as the outpost of an alien race known as the Antareans, a peaceful race of aliens who return to Earth after 10,000 years to retrieve their ancestors. Assuming human form, they inadvertently give away their extraterrestrial origin when ship captain Jack Bonner (Steve Guttenberg) sees one of them transform from a beautiful woman to her alien self. He agrees to help them retrieve the titular cocoons and return to their home planet, but the "life force" swimming pool is slowly being drained of its rejuvenating properties by a group of increasingly lively retirees. Cocoon is an affable comedy at heart, with a message about youth and immortality that bears a resemblance to the Spielberg-directed episode of The Twilight Zone: The Movie, Kick the Can, in which reminiscences about the joys of youth become a reality thanks to the magical interjection of the mysterious Mr. Bloom. A feel-good movie through and through, anyone watching who grew up in the 80s will undoubtedly find themselves asking as the credits roll, "What on earth happened to Steve Guttenberg?"