The birthday girl

Welcome to Eldey, an island with deadly secrets. Mona: a carefree artist, staying at the Cloister to work on her illustrations. Beth: the harried mother of a toddler, on the remote Welsh island for a weekend with her family. Charlotte: a reluctant stepmother who wanted a romantic getaway with her husband. One of them is a serial killer who poisoned four of her friends at her eleventh birthday party. They all fit the profile. Who will risk everything to kill again?