"It is everything you've dreamed of. It is nothing you expect". Cocoon was a sci-fi, comedy-drama released in 1985. The movie starred Don Ameche as Art Selwyn, Wilford Brimley as Ben Luckett, Hume Cronyn as Joe Finely, Steve Guttenberg as Jack Bonner, Jessica Tandy as Alma Finley, and Brian Dennehy as Walter). For the most part, the movie received positive reviews from critics, and was ultimately a successful venture for 20th Century Fox. It was successful enough to warrant a sequel, and Cocoon the Return was released in 1988).
Focusing on the original release, some 10,000 years prior, aliens from the planet Antarea set up an outpost on earth, known to earthlings as Atlantis. After Atlantis’ destruction, a number of Antareans are cocooned and left behind. Fast forward to 1985, and the Antareans have returned to earth, disguised as humans, to return their cocooned comrades back to Antarea. In the process, the Antareans rent a home with a pool, charge the pool with a special life force to be used to rejuvenate their cocooned brethren, and then they hire out a boat to help them find Atlantis and rescue those left behind.
Eventually, the captain of the chartered boat, Jack (played by Guttenberg), realizes they are aliens, but agrees to help them anyway after they explain their plight. The aliens end up finding the cocoons and stashing them in the swimming pool of their rented home. A few elderly residents in the area, who like to swim, quickly realize the youthful power of the water, and begin a fountain of youth physical transformation. When word gets out, so many old folks swim at once, that the life force is completely drained from the pool, and the cocooned Antareans are forced to remain on earth. However, the Antareans to offer a few of the old folks a chance to travel to Antarea with them and live forever, and a number of them take the Antareans up on their offer.