Computercide (1982)

The year is 1995 and Michael Stringer is the only private eye left on Earth. One day, he is assigned by a woman to investigate Eden Isle, a complex for people who want a perfect life started by an industrialist named Korter. Interestingly, Korter is found on a beach and is 20 years younger than he was before. When he gets into the complex, he is caught in a web of mystery.