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Shadowsea (Cogheart Adventure)



(4.5/5⭐️) “Even in the darkest places, working together, life could find a way.” A bittersweet end to the amazing Cogheart Series.


In the fourth and final installment of the Cogheart Adventure series, Lily, Robert, and Malkin find themselves in New York for New Years Eve with Lily’s father, John Hartman. Caddy is back for this adventure, too, along with her mother, Selena. When the children receive a plea for help from from a strange boy named Dane and his mouse, they can’t help but rush to discover secrets of his past. Their quest leads them to uncover the mystery of the Shadowsea Underwater Base and a chilling truth. Everyone on the Shadowsea was killed by a reannimation machine by Dane’s aunt—the villain of the story. The bodies were never accounted for and remain there, untouched, rotting. When Dane is kidnapped by his mechanical nurse, things take a turn for the worse, and their adventure leads them deep underwater where Caddy foretells that Dane will awaken the dead at midnight on New Year’s Eve.


This story was bittersweet. I’m rather sad that there won’t be anymore adventures to follow. I’ve grown to love Lily, Robert, and Malkin. But all good stories must come to an end. I found this to be a wonderful conclusion. It was great to see how far the characters have grown.

“Robert had learned that it was the mammoth random things that crashed across your life like tidal waves that made a difference and those were torments no amount of worry could predict.”


Unfortunately, I didn’t enjoy Shadowsea nearly as much as the others. I didn’t feel that it had as much edge-of-your-seat action. Skycircus was my ultimate favorite and felt more suspenseful than Shadowsea, which fell a little flat for me. The story was good, and a little predictable as they all are. That’s one of the things I like about the Cogheart Series. As an adult, I can generally predict what the motivations are, and where the story is headed.


The world Bunzl creates is enchanting. I’ve thoroughly enjoyed getting swept up into stories about airships, mechanicals, and cog hearts. The themes throughout each of his books are wonderful for middle grade readers. The theme throughout Shadowsea was obvious: the ones we love never really leave us even in death.


“The ones we’ve lost, they may be gone from the world, they may be gone from time, but they’re eternal now.”

I thought this theme was great for kids who have lost loved ones. But again, I appreciated the theme in Skycircus more.

It was refreshing getting to have an adventure set in NYC this time around. I loved the Cloudscrapers and Kid Wink, and their cool train car home. Their characters felt very genuine and fit right in with the setting, enriching the pages of the book. And it was fun getting to experience an underwater adventure at the Shadowsea base and, spoiler: zombies!! When the kids donned the scuba gear, I was totally pumped because it felt more unconventional compared to other adventures that kids have in books. One passage especially resonated with me. I felt it was one of the most beautiful passages in the book.

“Lily’s heart soared and she forgot her own predicament as she stared in wonder at the darting glowing fish. She had never seen anything quite so beautiful in all her life. They seemed almost miraculous. There were, she realized, greater things than herself and her friends in the wild corners of the world. Things to whom the water was not a danger, but home. Things that glowed with hope. Even in the darkest places, working together, life could find a way.”

Overall, I loved the story, enjoyed the others more, but am sad the series is over. I subtracted half of a star for what felt like an otherwise perfect story, simply because this story didn’t pack as much of a punch compared to the previous installments. I don’t want to say that I’m disappointed, as it was still engaging and enjoyable, but I guess I expected more out of a finale. I recommend this series at every opportunity. I’ve got friends with kids and I never hesitate to tell them about it. Share it with your kids, or even read it yourself. You’ll enjoy it!!

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