The three Hollow girls go missing without a trace on New Years Eve. One month later, they reappear with seemingly no memories of their time away. But the girls are different somehow.
Ten years later, the youngest Hollow Iris becomes concerned when her oldest sister Grey disappears. Is it happening all over again? Where did they go all those years ago?

This book seamlessly weaves fantasy, fairytales, and folklore into a thriller novel. It remind me of stories I used to hear in childhood, the morals of which were always to be wary of strange things in the dark.