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The Adventures of Kate #3
The Merlin Effect
FOR USE IN SCHOOLS AND LIBRARIES ONLY. An exciting hunt for sunken treasure...or a life or death encounter with an ancient legend?
256 pages, Paperback
First published September 15, 1994
8 people are currently reading
876 people want to read
About the author
T.A. Barron
72 books1,311 followersT.A. Barron grew up in Colorado ranch country and traveled widely as a Rhodes Scholar. He is the winner of the de Grummond Medallion for “lifetime contribution to the field of children’s and young adult literature” and many other awards. T. A. Barron is the author of more than 30 highly acclaimed books, many of which are international bestsellers. They include The Lost Years of Merlin (now being developed into a feature film), The Great Tree of Avalon (a New York Times bestselling series), The Ancient One (the tale of a brave girl and a magical tree), and The Hero’s Trail (nonfiction stories of courageous kids).
Though he’d dreamed as a young man of becoming a writer, he couldn’t find anyone to publish his first novel. He joined a successful business, eventually became president, then decided to try again. So in 1990, he surprised his business partners by moving back to Colorado to become a writer and conservationist.
In 2000, he founded a national award to honor outstanding young people who help their communities or the environment: the Gloria Barron Prize for Young Heroes, which honors 25 highly diverse, public-spirited kids each year. He recently produced a documentary film, Dream Big, profiling seven winners of the Barron Prize. When not writing or speaking, T. A. Barron serves on many boards including Princeton University, where he helped to create the Princeton Environmental Institute, and The Wilderness Society, which recently honored him with its highest award for conservation work. His favorite pastime is hiking, camping, or skiing in Colorado with his family.
Though he’d dreamed as a young man of becoming a writer, he couldn’t find anyone to publish his first novel. He joined a successful business, eventually became president, then decided to try again. So in 1990, he surprised his business partners by moving back to Colorado to become a writer and conservationist.
In 2000, he founded a national award to honor outstanding young people who help their communities or the environment: the Gloria Barron Prize for Young Heroes, which honors 25 highly diverse, public-spirited kids each year. He recently produced a documentary film, Dream Big, profiling seven winners of the Barron Prize. When not writing or speaking, T. A. Barron serves on many boards including Princeton University, where he helped to create the Princeton Environmental Institute, and The Wilderness Society, which recently honored him with its highest award for conservation work. His favorite pastime is hiking, camping, or skiing in Colorado with his family.
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Displaying 1 - 30 of 44 reviews
August 22, 2025
This book was published the year I was born, and it’s one of a handful that I have memories of my mom reading to me as a very small child (in good company with the likes of the LOTR trilogy, the early Harry Potter books, and most if not all of TA Barron’s Merlin books published in the 90’s). I remembered more of the feeling of the book, and of those quiet, formative evenings, than much about the plot. Nonetheless, my mom mailed me the 30 year old paperback we used all those years ago, and I’m happy to report that the book holds up after all these years (not literally, though - the paperback itself has been taped back together). The messages about reverence and awe for the beauty and mystery of the natural world still resonate. (I will note, however, that I don’t know or, frankly, care to know how well the oceanography holds up - if it doesn’t, don’t tell me). I found the Water Spirit passage and concept particularly striking.
I don’t generally read young adult (or younger) books, and I don’t tend to reread books, but reading this book again as an adult was a gift. The story itself is beautiful. But there’s something magical about the fact that this book and my mother’s love of stories about Merlin (much like the main character’s own father’s love for these stories) shaped me and taught me so much about how to move through the world with curiosity and compassion. I should call her.
I don’t generally read young adult (or younger) books, and I don’t tend to reread books, but reading this book again as an adult was a gift. The story itself is beautiful. But there’s something magical about the fact that this book and my mother’s love of stories about Merlin (much like the main character’s own father’s love for these stories) shaped me and taught me so much about how to move through the world with curiosity and compassion. I should call her.
December 25, 2023
The first section of this book is incredible and captivating. Really made me not set it down. But the second half felt rushed. Still a good read.
July 19, 2025
Found this with my dads stuff in the basement, solid read but can get kinda trippy
November 22, 2021
Young Kate is on a marine exploration expedition with her father. While out in a kayak one night, she rescues a whale whose flute is trapped in some wires for instruments attached to a buoy. It’s bleeding. Her father is trying to find an old treasure ship on the bottom of the sea, The Resurreccion. On it, Merlin was said to have put many treasures that King Arthur would need when he came back to life. Among the treasures was the Horn of Merlin, Serilliant. And in the Horn was an elixir that made one immortal. Kate comes to be on a boat during a storm and is swept overboard. She is caught in a giant whirlpool and ends up at the bottom of the sea on the Resurreccion with Merlin (only she knows him as Jeffrey of Beardsey). She meets his rival, the sorceress, Nimue, who is after the Horn. Merlin turns Kate into a fish so they can escape the sea demons and they find all of the treasures Emrys made for Winnowry’s father, the Merman king. They find all the treasures, but Nimue finds them as well. When there are volcanic eruptions on the sea floor, Merlin makes Kate leave with Serilliant. She throws it back into the water and the Merpeople take it to keep it safe. It was an okay book, a bit juvenile but I enjoyed it.
September 19, 2011
To me the Merlin Effect was filled with a mixture of both beauty and intelligence and that is what was able to draw my attention. I think the connection I shared with this book is that it talks about a person who barely spends time with her father and is mad that he isn't bothered by that fact. In my own life I rarely see my parents because they are always on business trips but when I want to go somewhere to get away from them suddenly they start saying no. Every time that happens I feels like I'm about to lose my mind. Anyway, this book is like Triple H but instead of being the King of Kings its rather the book of books. This story will live forever and there is no way and I mean NO WAY that I have been this satisfied after reading a book except of course Horrible History books.
June 26, 2011
A fresh take on Merlin and the King Arthur legend, but most certainly not a retelling. Instead, it is an original story with plenty of apparently well-researched references to the legend and even an appearance by Merlin himself.
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October 23, 2025Kate Gordon has traveled all the way to San Lazaro in Baja California ot help her fathr locate the sunken remains of theResurrection--a galleon wrecked in 1547 and believed to cradle in its belly a fortune in gold and silver. But as Kate is about to discover, there lays entombed in the dark and treacherous waters of San Lazaro a treasure far more valuable than anything Kate could ever imagined: a magical drinking horn from Arthurian times wihch--as legend would have it--led to the demise of the great wizard Merlin. Drawn by the power of the horn into an undersea world inhabited by strange and terrifying cratures, Kate must battle ancient forces to save her father's life...and her own.
December 21, 2021
I bought this book years ago, but never got around to reading it due to my ever expanding backlog of unread books.
This story moves quickly and I absolutely love the way it unfolds. It has the correct (as per me) amount of magic, myth, intrigue and science along with interesting characters.
The descriptions of Merlin's treasures and the glass house is superb, and the addition of nature into the story makes it shine.
Gonna read it to my daughter when she grows older.
This story moves quickly and I absolutely love the way it unfolds. It has the correct (as per me) amount of magic, myth, intrigue and science along with interesting characters.
The descriptions of Merlin's treasures and the glass house is superb, and the addition of nature into the story makes it shine.
Gonna read it to my daughter when she grows older.
June 13, 2023
This was a fun romp! I enjoyed the background information about Merlin and the ocean, though those plot elements were a strange combo that never fully gelled for me. Kate is a compelling character and the plot is nothing revolutionary. The fights toward the end were well-done, as was a character's reveal. I could have done without graduate student Terry, whose rivals-to-affection storyline with Kate felt out of place for a 13-year-old.
October 7, 2023
What a riot this book was. I did not exactly know what this book was about, but if you're one who likes oceanography, history, fantasy and myth, then...this is just the book for you! I honestly was a bit taken aback how quickly this book turned from a fairly straight tale about a research expedition into a fantastical epic, full of magic and demons and characters straight out of myth. One of those books that is a fun read in the moment, but probably not one I'd return to.
January 11, 2020
A quick and easy read that would enchant your teenager. Better still if you read it to them. The ballads and prophecies scan well for reading aloud. Sadly your audience might not be impressed by the cloak of invisibility, the giant chess game or the magic sword, though this was written long before the boy wizard.
This entire review has been hidden because of spoilers.
March 13, 2022
It's a normal book, with a normal quite stupid child (first 3 chapters) that OF COURSE gets involved in adventures on adventures.
Might be interesting read at an early age but I found too many coincidences in the book to be of my liking.
Might be interesting read at an early age but I found too many coincidences in the book to be of my liking.
October 13, 2018
Pretty good.
July 20, 2021
Interesting story although the first half & setup is more encouraging & exciting than the second half. Still it’s a quick, entertaining fantasy read.
December 25, 2025
The last part felt like it really rushed by a bit, but in that way that an old time fantasy movie would do. I finished the book in one sitting of about 3 hours and very much enjoyed it!
May 19, 2024
As she travels with her father while he explores the mysteries of Merlin, Kate gets sucked into the world of Merlin and his greatest nemesis. A fun adventure with some fun characters, even if it did get a bit predictable at times. 3/5 stars.
December 12, 2016
Wow, I wasn't expecting to enjoy this book as much as I did! Another good series from T A Barron. Thank you Mr. Barron
March 4, 2017
I stumbled onto this book somehow and I'm particularly fortunate. The protagonist, Kate, is real, courageous, and the storyline is fun and engaging. I just purchased the first two books in the series so more to follow.
November 22, 2023
The Merlin Effect was not my favorite of T.A. Barron’s “Adventures of Kate” trilogy when I was growing up: I was an Oregon girl, so my heart belonged to
The Ancient One
, which involves time travel in a Crater Lake-inspired setting. But I do recall rereading this book several times as a kid, so I must have found it pretty fun and fantastical. And I still do… especially when Kate gets swallowed by a whirlpool and finds herself alive at the bottom of the sea, on a miraculously preserved Spanish galleon with a dotty old monk!
IIRC, this is the book of the Kate trilogy that is most directly linked to preexisting mythopoetic fantasy stories: the legends of Arthur and Merlin. (Barron subsequently went on a Merlin craze, writing a 5-book series about the wizard in his youth.) But Barron combines and develops the existing folklore in unexpected ways. He takes the Welsh tradition of the Thirteen Treasures of the Isle of Britain, invents the idea that Merlin is safeguarding the treasures before King Arthur’s return, and then swaps out some of the traditional treasures for magical items of his own devising, most importantly a drinking horn that can grant eternal life. (Though, I was surprised to learn that another treasure, the “sword of light,” is not a rip-off of Star Wars lightsabers, but is directly from the medieval legends!)
After rereading The Merlin Effect as an adult, I suspect that it was also inspired by Barron’s having watched Disney’s The Little Mermaid one too many times with his own children. I mean, the book involves a wise old mer-king who lives in a shining undersea palace, and an evil sea-witch with black tentacles, and some demonic eels who serve the sea witch, and a sunken ship full of “treasures untold,” and an enchanted spiral seashell that everyone is fighting over. Obviously Barron mixed the Disney imagery up with a lot of other influences: Arthurian legend, sea shanteys, the 1990s fascination with marine biology and New Age mysticism. (This is very much a book for people who had a 'save the whales' bumper sticker and a cassette of humpback whale music.) But I do wonder if the success of The Little Mermaid is what originally prompted him to realize that kids would like to read about a plucky teenage girl on an undersea adventure.
IIRC, this is the book of the Kate trilogy that is most directly linked to preexisting mythopoetic fantasy stories: the legends of Arthur and Merlin. (Barron subsequently went on a Merlin craze, writing a 5-book series about the wizard in his youth.) But Barron combines and develops the existing folklore in unexpected ways. He takes the Welsh tradition of the Thirteen Treasures of the Isle of Britain, invents the idea that Merlin is safeguarding the treasures before King Arthur’s return, and then swaps out some of the traditional treasures for magical items of his own devising, most importantly a drinking horn that can grant eternal life. (Though, I was surprised to learn that another treasure, the “sword of light,” is not a rip-off of Star Wars lightsabers, but is directly from the medieval legends!)
After rereading The Merlin Effect as an adult, I suspect that it was also inspired by Barron’s having watched Disney’s The Little Mermaid one too many times with his own children. I mean, the book involves a wise old mer-king who lives in a shining undersea palace, and an evil sea-witch with black tentacles, and some demonic eels who serve the sea witch, and a sunken ship full of “treasures untold,” and an enchanted spiral seashell that everyone is fighting over. Obviously Barron mixed the Disney imagery up with a lot of other influences: Arthurian legend, sea shanteys, the 1990s fascination with marine biology and New Age mysticism. (This is very much a book for people who had a 'save the whales' bumper sticker and a cassette of humpback whale music.) But I do wonder if the success of The Little Mermaid is what originally prompted him to realize that kids would like to read about a plucky teenage girl on an undersea adventure.
August 26, 2010
This was not the best book to read immediately after The Hunting Games. The language felt stilted and overflowery for the target audience, the plot movement was choppy, and I didn't feel like the main character, a teenage girl, was well developed enough to absorb what the plot was requiring of her.
The storyline is about a teen girl named Kate who is with her father, a historian, on a scientific voyage with a woman who has is trying to find a fish that had previously been known as extinct. Her father is along on a tip on Merlin's horn, a supposedly magical horn that had been responsible for Merlin's death. The two purposes segue nicely even though the scientific crew with a historian looking for magical relics make for strange bedfellows in the story. Kate finds herself falling through an ocean whirlpool and in the land she discovers the secret to both the fish that apparently can live forever and the long-last legend of Merlin's horn.
What the author was deprived of in smooth storytelling he made up for with his homework. There was a lot of scientific language and information about antique-type relics that I would not expect to be so detailed in a juvenile fiction book.
If you like stories about Merlin, you will probably like this story. If you like stories about treasures at sea, you will likely enjoy this story. Other than that, the events of the story felt similar to some in the latter portion of the Percy Jackson series. A bit contrived at times. It came up lacking for me.
The storyline is about a teen girl named Kate who is with her father, a historian, on a scientific voyage with a woman who has is trying to find a fish that had previously been known as extinct. Her father is along on a tip on Merlin's horn, a supposedly magical horn that had been responsible for Merlin's death. The two purposes segue nicely even though the scientific crew with a historian looking for magical relics make for strange bedfellows in the story. Kate finds herself falling through an ocean whirlpool and in the land she discovers the secret to both the fish that apparently can live forever and the long-last legend of Merlin's horn.
What the author was deprived of in smooth storytelling he made up for with his homework. There was a lot of scientific language and information about antique-type relics that I would not expect to be so detailed in a juvenile fiction book.
If you like stories about Merlin, you will probably like this story. If you like stories about treasures at sea, you will likely enjoy this story. Other than that, the events of the story felt similar to some in the latter portion of the Percy Jackson series. A bit contrived at times. It came up lacking for me.
April 26, 2014
When I was a teen, my dad started traveling a lot for work. After a visit down to the States he came back with a copy of this book. Though it remains to this day the only book in the series I have ever read, I instantly fell in love with Kate.
The adventure is compelling and all-encompassing, it sucked me right in. I memorized the Ballad of the Resurrection (even reciting it as a piece for work) and spent countless hours imaging that I was, in fact, Kate.
This book is the reason I named my cat Nimue, and if that isn't indicative of the story's impact on my life, I don't know what is.
The adventure is compelling and all-encompassing, it sucked me right in. I memorized the Ballad of the Resurrection (even reciting it as a piece for work) and spent countless hours imaging that I was, in fact, Kate.
This book is the reason I named my cat Nimue, and if that isn't indicative of the story's impact on my life, I don't know what is.
October 16, 2016
This book starts off really slow. There's a lot of talking about Merlin in the beginning with nothing actually happening. And then once things do starting happening, there's nothing exciting or interesting going on until the very end where nothing gets explained. This felt like such a pointless read. And I feel it really could have been so much better. Like what if Kate falls down the whirlpool the first time and learns about Merlin through her adventures instead of spending a whole chapter of her father just talking to her about it?
December 18, 2008
Kate is on vacation with her father to discover a sunken Spanish ship. But as she delves deeper into the legend of the boat she realizes that it may contain the mysterious drinking horn of Arthurian legend that led to the demise of the wizard Merlin. Kate plunges into an undersea world of creatures and foes in an attempt to save her father and her own free will she will have to succeed where Merlin failed.
June 6, 2016
This book had some interesting new ideas, and I definitely liked how the book was kind of like putting clues together about Merlin and his treasures. I liked the modern twist on an ancient legend, but I thought that in some parts they made Merlin seem a little like a silly old man, instead of being invincible and timeless and wise. I also thought that the part about how Kate's father seemed to care so little about her was sad.
December 21, 2008
This book is set in a researchers camp off the coast of Baja California where the main teenage protagonist's dad is trying to find something...it turns out to be freaking Merlin's boat/hall/whatever as his daughter finds it and must help save everything and such. I didn't really enjoy this one if'n you couldn't tell, pardner. Carry on.
March 17, 2009
I loved this book as a 7th grader and recently procured a copy of my own. Although I love the thought, the characters, and the organization of the text, certain sections of the text separated me from the story because I became too involved in writing technique. Nonetheless... it is still a wonderful book and supplied me with many daydreams as a youth.
November 7, 2013
Not good. Lots of holes, even for a YA fantasy. And the dialogue. It's pretty bad. The style is fine. He's not a bad writer, just cheesy and a real lack of attention to the depth of his world. I know, it's a kids book. But it wasn't written by a kid, right? Riiiiight. So we can't excuse him from scrutiny. Sorry.
July 8, 2016
One day the sun will fail to rise
The dead will die
And then
For Merlin's Horn to find its home
The ship must sail again.
This book was one of my all-time favorites as a child, and it still is today. Kate's story is compelling, interesting, and gripping. This book is timeless and it is definitely a story I will treasure.
The dead will die
And then
For Merlin's Horn to find its home
The ship must sail again.
This book was one of my all-time favorites as a child, and it still is today. Kate's story is compelling, interesting, and gripping. This book is timeless and it is definitely a story I will treasure.
December 1, 2009
I love this book! I love how all of T. A. Barron's books are really unique...I mean...a killer whirlpool that guards Merlin's Horn? Amazing!
This entire review has been hidden because of spoilers.
Want to read
December 3, 2008Per Justin
Displaying 1 - 30 of 44 reviews