In a post-apocalyptic future, humanity survives in a vast and ancient system of underground tunnels known as the city of Ember, once a safe haven, now languishing in darkness. The energy that powers the city is waning, and its inhabitants face constant blackouts and food shortages. Young Lina Mayfleet, with a heart full of hope and ambition, longs to be a Messenger, a job that allows her to explore and discover more about her mysterious city.
Meanwhile, her friend Doon Harrow, filled with ingenuity and determination, seeks answers about how the generator that keeps the city afloat works. They soon realize that the situation is much more dire than they imagined; the city is on the brink of total collapse. After finding an ancient and enigmatic document, Lina begins to decipher clues that could lead to the salvation of Ember and its citizens. As they delve into the secrets of the past, the two friends must overcome dangerous obstacles and uncover the truth about their home before the light goes out forever.
With time running against them, Lina and Doon embark on an epic adventure filled with challenges, friendship, and bravery. Together, they must unravel the mystery surrounding their city and find a way out to the world that might lie beyond the shadows. Will they escape in time, or will they be trapped forever in the darkness?