SOLVED. Thriller - Group of people brought to an island to take part in a sadistic game, for revenge. Potential spoilers.

[Fiona]

So - first off, this is NOT And Then There Were None, though it fits with that genre.

Read this early-mid 2000s. A group of people are brought to an island and take part in an increasingly sadistic game. There's a series of challenges, and they're chosen to take part in them as both the victim and the perpetrator. If the person chosen to inflict the punishment on another guest doesn't, there's a penalty.

Potential spoilers from here.

I believe the book ends with a couple of the "guests" managing to band together and take out the island's owner and his staff.

Honestly, not a great book, but cannot remember it and it's bothering me - hopefully someone out there has come across it as well!

[Fiona]

Found it - just occasionally the physical bookshelves come through!

The Game