Millie Bobby Brown’s debut novel is underway.

The “Stranger Things” star just landed a deal with William Morrow, an imprint of HarperCollins, who will publish the actress’ historical novel, NINETEEN STEPS, inspired by her own family history.

Brown was persuaded to write the book based on her personal connection to the Bethnal Green Tube Disaster- her grandmother Ruth survived the accident- which became the largest single loss of civilian life in the U.K. during World War II.

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The official synopsis for the book reads: An epic story of love, loss, and secrets, NINETEEN STEPS tells the story of 18-year-old Nellie Morris, who lives with her family in Bethnal Green while the second world war rages on around them. With a job  assisting the mayor and nights spent at the local pub with her best friend, Nellie does her best to hold onto remnants of normalcy. After a chance encounter with Ray, an American airman stationed nearby, Nellie becomes enchanted with the idea of a broader world. Just when Nellie begins to embrace an exciting new life with Ray, a terrible incident occurs during an air raid one evening, and the consequences are catastrophic. As the truth about that night is revealed, Nellie’s world is torn apart. When it seems all hope is lost, Nellie finds that, against all odds, love and happiness can triumph.

“Inspired by my Nanny Ruth, this book is very personal and close to my heart,” Brown, 19, said. “I grew up listening to stories about her time living through the war. I’m honoured to keep her story alive.”

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Meanwhile, Liz Stein, the Executive Editor at William Morrow who negotiated the deal, said Brown’s novel is “a tender, inspiring story about female resilience and the human spirit.

“Both heart-warming and heart-breaking, it’s a novel that portrays the strength and courage we find in family, friendship, and community,” she continued. “I was incredibly moved by the haunting, true tragedy at the core of the novel and enchanted by the unforgettable portrait of love in the time of war.”

NINETEEN STEPS will be published on September 12, 2023.