I read this while I was on holiday and I got completely sucked in. It's an immersive and epic story with well-drawn, complex characters. I think it would make a fantastic book to discuss for a book club if your book club doesn't mind a longer read. 

I also talk about this book in episodes 54 and 55 of The Bookcast Club podcast. 

Ep 54: https://www.thebookcastclub.com/podcast/episode/4a6e05b0/54-book-club-the-mermaid-of-black-conch-by-monique-roffey

Ep 55: https://www.thebookcastclub.com/podcast/episode/4c3f375e/55-upcoming-book-to-movie-adaptations