New troubles loom for Saffy, her brother Connor, and their friend Faro, not just because the Kraken - an ancient monster of the deep - has threatened to destroy Ingo unless the Mer give it over their young. A new danger is rising, with aspiring leader Ervys gaining strength by encouraging prejudice those who aren't full-blooded Mer.
Faro's mentor, Saldowr, believes the people of Ingo have another option in Saffy, who entered the deep and managed to survive - an impossible feat all but a handful of the ocean's inhabitants. He presents Saffy with the monumental task of returning to fight and defeat the kraken. Despite the brewing tensions between Ingo and Air, Saffy and Connor agree to help, on the condition that they're allowed to see their father (who traded life as a human to become Mer) upon their return. Armed only with Granny Karne's rowan seeds and Saldowr's magical mirror, Saffy, Connor, and Faro embark on a perilous journey inside the mouth of a whale.
While it's easy enough to dive right into THE DEEP without reading the first two books in Helen Dunmore's Ingo series, I highly recommend all of them. I was so eager to follow the events of Saffy's life and discover the source of her family's connection to the sea, I gobbled up these books up in a matter of days. THE DEEP is a page-flipping installment which takes the three main characters to the edge of an unknown world, forcing them to confront their deepest fears against a treacherous enemy.