It's Alive III: Island of the Alive

The monster babies have been placed by court order on a deserted island so that they can live out their lives as far away from normal humans as possible without killing them. Enraged by the cynicism toward, and the exploitation of, the monster babies by both the legal system and the media, the man who is responsible for them leads an expedition to the island in order to free them.

It's Alive III: Island of the Alive is a 1987 horror sci-fi movie directed by Larry Cohen, starring Karen Black, James Dixon, Laurene Landon. It holds an IMDb rating of 4.9/10 from 2,501 votes and runs 1h 35m.