They built a wall to keep the ocean out. They just forgot to ask which side of it we were on.

Ndidi is fourteen years old. She has lived her whole life in Makoko - the floating city of stilt houses on the lagoon at the edge of Lagos, Nigeria. She has taught herself, at the kitchen table, to read climate-science papers, satellite maps, and the small print on the planning notices the men in the white shirts have started taping to the schoolhouse door.

One morning the notice she has been dreading arrives. The new wall - a kilometre of glass and concrete that the developers say will save the rich quarter on the other side from the rising sea - is going to be built. Down the spine of her neighborhood. Through her grandmother's kitchen.

Makoko is on the wrong side of the wall.

High Water is the story of what one teenage girl did when the world quietly decided her family did not count. Of the flotilla she organised on a single radio. Of the question she asked the chief, on a livestream, in front of the world. Of the small green light that started pulsing on a cracked tablet on her bedside table the night the wall went up, and the four other young people, on four other coasts, who were - though Ndidi did not yet know it - listening.

For readers ages 13 and up. A propulsive, true-to-the-science novel about a real city, a real crisis, and the kind of brave a fourteen-year-old has to learn how to be when nobody else is going to learn it for her.

This is Book One of The Reckoning, a six-novel cycle in the Climate Keepers universe. Each book stands alone; together they tell the story of one year on five coasts. Book Two: Dry (Rajasthan). Book Three: Bleach (Cartagena). Book Four: Greenwash (Malmö). Book Five: The Last Island (Samoa). Finale: The Gathering (Belém).

"We are not your climate's afterthought."

Find your rock. Come back to it. Teach somebody the names.