Promises Stronger Than Darkness marks the final installment of the international bestselling author Charlie Jane Anders's absolutely heart-stopping YA series, Unstoppable. They're the galaxy's most wanted—and our only hope.

When Elza became a space princess, she thought she'd be spending her time at the palace, wearing gorgeous couture and soaking up everything there is to know—but instead, she's on the run, with everyone hunting for her and her friends.

Rachael followed her best friend Tina on the adventure of a lifetime—but now Tina's gone, and Rachael's the only one keeping her friends together, as they go on a desperate quest to save everyone from an ancient curse.

Rachael, Elza, and their friends have found one clue, one shining mysterious chance to stop the end of the world. And that takes them back to the second-to-last place they'd want to be: enlisting the aid of Captain Thaoh Argentian, the woman who stole Tina's body (and who now seems to be relishing a second chance at teenage chaos and drama, instead of living up to her legacy as an intrepid heroic commander).

With only a ragtag band of misfits, crewmates, earthlings, friends, lovers (and one annoying frenemy), the Unstoppable Crew are up against the universe—and they soon find that in order to survive, they may have to cross a line they vowed never to cross.

In the vein of The Pisces and The Vegetarian, Chlorine is a debut novel that blurs the line between a literary coming-of-age narrative and a dark unsettling horror tale, told from an adult perspective on the trials and tribulations of growing up in a society that puts pressure on young women and their bodies. It is a powerful, relevant novel of immigration, sapphic longing, and fierce, defiant becoming.

Ren Yu is a swimmer. Her daily life starts and ends with the pool. Her teammates are her only friends. Her coach, her guiding light. If she swims well enough, she will be scouted, get a scholarship, go to a good school. Her parents will love her. Her coach will be kind to her. She will have a good life. But these are human concerns. These are the concerns of those confined to land, those with legs.

Ren grew up on stories of creatures of the deep, of the oceans and the rivers. Ones that called sailors to their doom. Ones that dragged them down and drowned them. Ones that feasted on their flesh. Ones of the creature that she's always longed to become: mermaid.

Ren aches to be in the water. She dreams of the scent of chlorine—the feel of it on her skin. And she will do anything she can to make a life for herself where she can be free. No matter the pain. No matter what anyone else thinks. No matter how much blood she has to spill.