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Children's Fiction Mysteries & Detective Stories

Aggie Morton, Mystery Queen: The Seaside Corpse

by (author) Marthe Jocelyn

illustrated by Isabelle Follath

Initial publish date
Oct 2023
Mysteries & Detective Stories, European, Law & Crime
Recommended Age
10 to 18
Recommended Grade
5 to 12
  • Hardback

    Publish Date
    Nov 2022
    List Price
  • Paperback / softback

    Publish Date
    Oct 2023
    List Price

Classroom Resources

Where to buy it


For young detective Aggie Morton and her friend Hector, an opportunity to dig up fossils becomes even more thrilling when a corpse washes ashore in this fourth book in the Aggie Morton, Mystery Queen series, inspired by the life of Agatha Christie as a child and her most popular creation, Hercule Poirot. For fans of Enola Holmes and ages 10 and up.

After an invigorating but not exactly restful trip to a Yorkshire spa during which she survived a near brush with death and foiled a murderer, aspiring writer Aggie Morton and her friend Hector are thrilled to have the opportunity to stay at a camp by the sea and watch real paleontologists at work. The famed husband and wife team of the Blenningham-Crewes are about to become even more famous with the recovery of the fossilized bones of an ichthyosaur from the sea by Lyme Regis. This news has already caught the attention of an American millionaire, a British museum and a travelling circus owner, who each want the bones for their own collections. Tensions are running high throughout the camp, from the cook, to the collectors, to the Blenningham-Crewes themselves, and become downright dangerous after Aggie and Hector make a discovery of their own: a body on the beach. Not a fossil, but a human body.

About the authors

Marthe Jocelyn is the award-winning author and illustrator of over thirty-five books for babies, kids and teens. Her illustrated books have been shortlisted for both the Governor General’s Literary Award and the Marilyn Baillie Picture Book Award. In 2009 she was the recipient of the prestigious Vicky Metcalf Award for her body of work. One Red Button and One Piece of String are the result of her lifelong obsession with scraps, and her delight in surprising the reader with unexpected details. Originally from Toronto, Marthe settled in Stratford, Ontario, after a thirtyyear stretch in New York. For more information, visit

Marthe Jocelyn's profile page

Isabelle Follath's profile page


  • Short-listed, Ruth and Sylvia Schwartz Children’s Book Awards
  • Winner, Edgar Allan Poe Award for Best Juvenile Novel
  • Short-listed, The Crime Writers of Canada Awards of Excellence - Best Juvenile or YA Crime Book

Editorial Reviews

WINNER of the 2023 Mystery Writers of America Edgar Allan Poe Award for Best Juvenile Mystery!

"[E]nthralling. . . . [A] good collection of information always goes down better with a good story to hang it on! The Seaside Corpse has both elements in spades, making a winning combination." CM Reviews

"Jocelyn is funny without descending to parody. Her control of language is as precise as the rational methods which Agatha and Hector applying to solving mysteries. . . . [T]here is plenty of rewarding material here for readers, young and older, who enjoy informed, literate, and inventive fun." —Imaginary Elevators

Other titles by Marthe Jocelyn

Other titles by Isabelle Follath