Cocoon (1985)

In Cocoon, a group of elderly people living in a retirement community stumble upon a swimming pool that rejuvenates them. They soon realize that the pool is a hiding place for a group of friendly extraterrestrials who are trying to retrieve cocoons containing their companions. As the elderly protagonists continue to visit the swimming pool, they experience renewed energy and youthfulness, leading to a series of heartwarming and humorous events.