From the No.1 New York Times bestselling author of Lore and The Darkest Minds trilogy comes this stunning series opener inspired by Arthurian legend and fuelled by love, revenge and pure adrenaline - cementing Alexandra Bracken's status as one of the top fantasy authors writing today. Tamsin Lark didn't ask to be a Hollower. As a mortal with no magical talent, she was never meant to seek legendary relics from the ancient crypts of dark sorceresses. But after her thieving foster father disappeared without so much as a goodbye, it was the only way to keep herself - and her brother, Cabell - alive. Ten years later, rumours are swirling that her guardian vanished with a powerful ring from Arthurian legend, igniting Tamsin's hope of freeing Cabell from a curse that threatens them both. But they aren't the only ones who covet the ring . As word spreads, greedy Hollowers start circling, and Tamsin is forced into an uneasy alliance with her rival Emrys just to survive.

Their race for the ring leads them across modern-day England into Avalon, but the misty otherland is nothing like the legends claim. As the mystery rotting the heart of Avalon consumes them, and they come no closer to finding the ring, Tamsin begins to fear she won't just lose her brother - she'll lose her one chance to uncover the secret of who she truly is.