Suggestions: Tropical holiday island which is controlled by a religious group

[VidyaForever]

Hello, I am looking for some book, which has plot as follows:

A person visits tropical island (either was sent there for some reason or is on a vacation), meets a few cool people, everything seems nice and relaxing untill he discovers that there's in fact a dark sect that controls the island and does some creepy rituals...

 

 

Any suggestions? There's a few movies with theme similar to this, but I cant think of any books

[frankie]

The only thing that comes to mind is a book by Alex Garland.. 

[Madeleine]

I thought of that too - the Beach.