For 150 years, Caldonbrae Hall has loomed high above the Scottish cliffs as a beacon of excellence in the ancestral castle of Lord William Hope. A boarding school for girls, it promises that its pupils will emerge 'resilient and ready to serve society'.
Into its illustrious midst steps Rose Christie, a 26-year-old Classics teacher and new head of department. Rose is overwhelmed by the institution: its arcane traditions, unrivalled prestige, and terrifyingly cool, vindictive students. Her classroom becomes her haven, where the stories of fearless women from ancient Greek and Roman history ignite the curiosity of the girls she teaches and, unknowingly, the suspicions of the powers that be.
But as Rose uncovers the darkness that beats at the very heart of Caldonbrae, the lines between myth and reality grow ever more blurred. It will be up to Rose - and the fierce young women she has come to love - to find a way to escape the fate the school has in store for them, before it is too late.