Savage Island — Bryony Pearce

When reclusive millionaire Marcus Gold announces that he's going to be staging an "Iron Teen" competition on his private island in the Outer Hebrides, teenagers Ben, Lizzie, Will, Grady and Carmen sign up - the prize is one million pounds … each. But when the competition begins, the group begin to regret their decision. Other teams are hunting their competitors and attacking them for body parts. Can the friends stick together under such extreme pressure to survive? When lives are at stake, you find out who you can really trust...
A Red Eye horror novel for teens, this gripping YA thriller story is full of fast-paced action.