The 2019 Green Earth Award-Winning trilogy opener is now available in trade paperback! Forty years after the earth was devastated by massive flooding, four children on one small sailboat must flee corrupt authorities and overcome the dangers of the sea that drowned their world. Twins Will and Annalie thought the hardest part about this year was going to be their separation when bookish Annalie began life at a prestigious Admiralty-run boarding school and avid sailor Will stayed behind in the flood-damaged slums. But that was before the Admiralty raided their father's engineering workshop. Before they sent a questioner to threaten Annalie at school. Before their father disappeared, leaving a single coded clue to his destination. Desperate to find their father, the twins set out in the family's small sailboat. But though they are both experienced sailors, they have no idea what dangers the sea has in store for them. With The Flooded Earth, Mardi McConnochie opens her middle-grade cli-fi saga at top speed, drawing readers into a race against pirates, authorities, and the sea itself in a not-so-distant future full of new technology and old human failings.

Twins Annalie and Will Wallace return in this action-packed sequel to the stunning cli-fi novel The Flooded Earth It's been months since their father, Spinner, disappeared after the Admiralty tore apart his workshop and sent him into hiding, but Annalie and Will are determined to find him, whatever the cost. With the help of new friends Essie and Pod (and talking parrot, Graham), the siblings use the decoded clues Spinner left behind to track his movements, sailing around the world in search of his old scientific colleagues. But the Admiralty is still in hot pursuit, and the sea might be the biggest threat of all. As the children battle massive storms, menacing marines, and pirates out to steal anything (and anyone) they can, the twins and their friends discover new levels of strength, determination, and ingenuity within themselves. They also begin to wonder if they'll ever catch up to Spinner, or if the dangers they encounter along the way will seal their fates first. The Castle in the Sea is the sequel to the 2019 Green Earth Award-winning novel The Flooded Earth