Good Girls Die First by Kathryn Foxfield

Mind games. Murder. Mayhem. How far would you go to survive the night?

Blackmail lures sixteen-year-old Ava to the derelict carnival on Portgrave Pier. She is one of ten teenagers, all with secrets they intend to protect whatever the cost. When fog and magic swallow the pier, the group find themselves cut off from the real world and from their morals. As the teenagers turn on each other, Ava will have to face up to the secret that brought her to the pier and decide how far she's willing to go to survive.

For fans of Karen McManus' One of Us Is Lying, Agatha Christie's And Then There Were None, and films like I Know What You Did Last Summer.