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Monster Down Deep
Not yet published
Expected 2 Jun 26A missing diamond necklace with a million dollar reward attracts 2 beachcombing children, who instead find what could just be the discovery of the century
An uplifting middle-grade adventure perfect for fans of Jessie Burton, Hannah Gold’s The Last Bear, and books by Katya Balen
I am the one they call the Monster Down Deep.
Except... I am not really a monster. I am just the Very Afraid Fish.
Somewhere off the coast of San Diego, the yacht of billionaire Clifton Royce III has capsized. While most of the vessel’s belongings have been reclaimed, one piece remains a 74-carat diamond necklace, worth over $50 million dollars. And for the person who finds this gem, there is a $1 million reward up for grabs.
No one is more determined to find the necklace than 11-year-old Cassie Stein. Her dad’s beloved aquarium is on the brink of financial ruin, and that money could be the answer to all their problems. Armed with her trusty metal detector, Sylvia, Cassie begins her search.
But while hunting for the treasure, she discovers something that may be even more valuable than the diamond. A fish, unlike any she has ever seen before. One that seems to understand her every word perfectly. His name is Blue, and he desperately needs Cassie’s help.
As news of her once-in-a-lifetime discovery spreads, however, Cassie is torn between two impossible protect Blue and help him find his way home… or embrace the fame and fortune that could change her life forever.
An uplifting middle-grade adventure perfect for fans of Jessie Burton, Hannah Gold’s The Last Bear, and books by Katya Balen
I am the one they call the Monster Down Deep.
Except... I am not really a monster. I am just the Very Afraid Fish.
Somewhere off the coast of San Diego, the yacht of billionaire Clifton Royce III has capsized. While most of the vessel’s belongings have been reclaimed, one piece remains a 74-carat diamond necklace, worth over $50 million dollars. And for the person who finds this gem, there is a $1 million reward up for grabs.
No one is more determined to find the necklace than 11-year-old Cassie Stein. Her dad’s beloved aquarium is on the brink of financial ruin, and that money could be the answer to all their problems. Armed with her trusty metal detector, Sylvia, Cassie begins her search.
But while hunting for the treasure, she discovers something that may be even more valuable than the diamond. A fish, unlike any she has ever seen before. One that seems to understand her every word perfectly. His name is Blue, and he desperately needs Cassie’s help.
As news of her once-in-a-lifetime discovery spreads, however, Cassie is torn between two impossible protect Blue and help him find his way home… or embrace the fame and fortune that could change her life forever.
304 pages, Paperback
Expected publication June 2, 2026
1 person is currently reading
21 people want to read
About the author
Amy Fellner Dominy
11 books259 followersHi! I write contemporary books for kids and teens and anyone who loves adventure, nature, laughter and a bit of magic. Coming in 2026: MONSTER DOWN DEEP, a middle grade adventure and A HOUSE WITH NO DOOR, a picture book about the harvest holiday of Sukkot. For news, giveaways and sneak peeks, sign up for my monthly newsletter at www.amydominy.com/newsletter. Thanks for following me here!
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Displaying 1 - 5 of 5 reviews
Review of advance copy received from Edelweiss+
E ARC provided by Edelweiss Plus
Cassie and her father live on the coast of Southern California, where her father is an aquarist for the small Mayim Aquarium. Her mother, who was also interested in the well being of the ocean and its creatures, was killed in a car accident when Cassie was three. There has recently been a yacht crash in the area that resulted in the loss of a lot of expensive jewelry, and the Royce family has offered a million dollar reward for the return of a particularly elaborate $50 million dollar necklace. Cassie, along with her Hunter Pro Series 2 metal detector named Sylvia (after marine biologist Sylvia Earle), is determined to find the item. What she finds instead is Blue, a very odd fish, whose point of view is shared in some chapters. Blue is caught in a fishing net and a lot of seaweed, and seems to understand when Cassie communicates with him. Cassie is not happy to see a “Mystery Thief", a boy her age who is also looking for the necklace, but gets to know TJ, who is staying along the beach with his uncle while his father and pregnant mother are back home in Carlsbad while the mother is on bedrest. Cassie spends a lot of time on the beach, nominally supervised by local artist Miss Mary, and when she sees Blue being menaced by a seven gill shark, she immediately goes to her father for help. Unfortunately, he is in a very important meeting with the new directors of the aquarium, but manages to save Blue. Since Blue is very unusual, he becomes a cause celebre in the news, but also isn’t treated well by the new directors. Will Cassie be able to continue to search for the necklace but also save Blue?
Strengths: Treasure hunts are always popular, and the ocean is an interesting place for them, which we see in novels like Rodriguez’s Treasure Tracks or Collard’s Double Eagle. Combining this activity with saving an unusual fish and an interesting small aquarium makes for an intriguing story. I was glad to see that Cassie didn’t fight with TJ the entire time, but learned to work with him. There is a little bit of friend drama with two of Cassie’s sometimes friends, both realistically named Emma! Cassie’s family is Jewish (as are many of Dominy’s characters, going back to her 2011 OyMG), as are the owners of the aquarium, and I enjoyed how the Jewish concept of tikkun olam was explained and demonstrated.
Weaknesses: This almost verged into fantasy, with Blue seeming to understand Cassie’s communication, but it remains a realistic fiction book. While it is admirable that Cassie wants to save Blue, releasing him back to a dangerous situation in the ocean while ignoring the recommendations of her father made me uncomfortable. It didn’t help that the dead parent trope was embraced even though it did nothing to enhance the plot. The ending is happy, but a little unbelievable.
What I really think: This is a good choice for readers who enjoyed aquatic preservation adventures like Dimopoulos' Turn the Tide, Baskin’s and Polisner’s Consider the Octopus, Kelly’s Three Blue Hearts, or Pyron’s Octopus Moon.
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Cassie and her father live on the coast of Southern California, where her father is an aquarist for the small Mayim Aquarium. Her mother, who was also interested in the well being of the ocean and its creatures, was killed in a car accident when Cassie was three. There has recently been a yacht crash in the area that resulted in the loss of a lot of expensive jewelry, and the Royce family has offered a million dollar reward for the return of a particularly elaborate $50 million dollar necklace. Cassie, along with her Hunter Pro Series 2 metal detector named Sylvia (after marine biologist Sylvia Earle), is determined to find the item. What she finds instead is Blue, a very odd fish, whose point of view is shared in some chapters. Blue is caught in a fishing net and a lot of seaweed, and seems to understand when Cassie communicates with him. Cassie is not happy to see a “Mystery Thief", a boy her age who is also looking for the necklace, but gets to know TJ, who is staying along the beach with his uncle while his father and pregnant mother are back home in Carlsbad while the mother is on bedrest. Cassie spends a lot of time on the beach, nominally supervised by local artist Miss Mary, and when she sees Blue being menaced by a seven gill shark, she immediately goes to her father for help. Unfortunately, he is in a very important meeting with the new directors of the aquarium, but manages to save Blue. Since Blue is very unusual, he becomes a cause celebre in the news, but also isn’t treated well by the new directors. Will Cassie be able to continue to search for the necklace but also save Blue?
Strengths: Treasure hunts are always popular, and the ocean is an interesting place for them, which we see in novels like Rodriguez’s Treasure Tracks or Collard’s Double Eagle. Combining this activity with saving an unusual fish and an interesting small aquarium makes for an intriguing story. I was glad to see that Cassie didn’t fight with TJ the entire time, but learned to work with him. There is a little bit of friend drama with two of Cassie’s sometimes friends, both realistically named Emma! Cassie’s family is Jewish (as are many of Dominy’s characters, going back to her 2011 OyMG), as are the owners of the aquarium, and I enjoyed how the Jewish concept of tikkun olam was explained and demonstrated.
Weaknesses: This almost verged into fantasy, with Blue seeming to understand Cassie’s communication, but it remains a realistic fiction book. While it is admirable that Cassie wants to save Blue, releasing him back to a dangerous situation in the ocean while ignoring the recommendations of her father made me uncomfortable. It didn’t help that the dead parent trope was embraced even though it did nothing to enhance the plot. The ending is happy, but a little unbelievable.
What I really think: This is a good choice for readers who enjoyed aquatic preservation adventures like Dimopoulos' Turn the Tide, Baskin’s and Polisner’s Consider the Octopus, Kelly’s Three Blue Hearts, or Pyron’s Octopus Moon.
https://msyinglingreads.blogspot.com/...
https://msyinglingreads.blogspot.com/...
https://msyinglingreads.blogspot.com/...
https://msyinglingreads.blogspot.com/...
https://msyinglingreads.blogspot.com/...
https://msyinglingreads.blogspot.com/...
https://msyinglingreads.blogspot.com/...
November 27, 2025
This is simply the loveliest book—clever, touching and literally laugh out loud funny in parts. Everything about it is delightful and five stars aren’t enough.
December 5, 2025
Digital ARC. Middle grade children’s book. Adventure and coming of age story.
Review of advance copy received from Publisher
Review forthcoming. A middle grade story told to perfection with humor and so much humanity.
Review of advance copy received from Publisher
Review to come.
Absorbing, fun, and wonderfully unique!
Absorbing, fun, and wonderfully unique!
Displaying 1 - 5 of 5 reviews