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Lock & Mori

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About The Book

In modern-day London, two brilliant high school students meet. A murder will bring them together. The truth very well might drive them apart.

You know their names. Now discover their beginnings.

Someone has been murdered in London’s Regent’s Park, and sixteen-year-old Lock has challenged his classmate Mori to solve the crime before he does. His only rule: they must share every clue with each other.

Mori reluctantly agrees, but what begins as fun and games quickly becomes sinister. As she gets closer to solving the case—and more and more drawn to Lock—she discovers that the murder is connected to her own past. Now she’s keeping secrets from Lock, her family, and her best friend, secrets with dire consequences.

To save herself and loved ones, Mori is prepared to take matters into her own hands. Will Lock be standing by her side when it’s all over? That’s one mystery Mori cannot solve.

About The Author

Photograph © Ari Nordhagen

Heather W. Petty has been obsessed with mysteries since she was twelve, which is when she decided that stories about murders in London drawing rooms and English seaside villages were far superior to all other stories. She is the author of the Lock & Mori series. She lives in Reno, Nevada, with her husband, daughter, and four hopelessly devious cats. You can visit her online at

Product Details

  • Publisher: Simon & Schuster Books for Young Readers (September 13, 2016)
  • Length: 272 pages
  • ISBN13: 9781481423045
  • Grades: 9 and up
  • Ages: 14 - 99
  • Lexile ® 890L The Lexile reading levels have been certified by the Lexile developer, MetaMetrics®

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Raves and Reviews

"Mystery lovers will be pleased to have this whodunit, which is neither Victoriana nor steampunk."

– Kirkus Reviews

“A unique spin on a familiar tale makes Lock & Mori wise, witty and engaging. Author Heather W. Petty is a force to be reckoned with.”

– Ellen Hopkins, author of CRANK, TRICKS, AND TRAFFICK

"Darkly atmospheric, and the stakes are high."

– Booklist

"Mori is a well-developed, multidimensional protagonist and a lively narrator. Lock is just as intriguing...The ending will leave readers wanting more from these two mystery mavens."

– School Library Journal

"[A] quick-moving mystery distinguished by clear writing, memorable imagery, and some keen insights into human fragility."

– Publishers Weekly

“True to canon, this sleuthing tale is rife with intrigues, puzzles, and vivid danger. Read at your own peril – nothing is more electrifying than the hunt for truth.”

– The Christian Science Monitor

"[T]een readers will enjoy the dialogue, the dark mystery, and of course, the romance."

– School Library Connection

Awards and Honors

  • Kansas NEA Reading Circle List High School Title

Resources and Downloads

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More books from this author: Heather W. Petty

More books in this series: Lock & Mori