This book, by Camilla Way, is in a single word, very creepy. I had a lot of anxiety reading it and felt a little sick to my stomach at times. It explores the darker side of female friendships and is also pretty upsetting, but I would still recommend it. It alternate between the stories of two girls (at age 17 and then in their early thirties). You’ll find yourself nervous and a little disturbed but you also won’t be able to put it down. If you loved The Girl on the Train, this one is for you.