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The Secret of the Sapphire Sentinel
In the twilight world of Glimmerbight, fourteen-year-old Gen Lightworth dreams of restoring the Inn at the Amethyst Lantern. But an ancient evil's lingering scars awaken new threats from unexpected corners.
Summoned by the mysterious Gallant Twilight Society-a network of heroic animals-Gen journeys beneath the waves into hidden lairs pulsing with bioluminescent secrets. With her loyal team, the Fireflies, she confronts lost legacies, mutated monsters, and shadowy figures from the past.
When a vibrant yet unsettling new apothecary arrives, secrets multiply and trust frays. And as danger closes in, Gen learns the true weight of leadership and the strength of friendship.
Filled with wonder, bravery, and the luminous bonds of community, The Secret of the Sapphire Sentinel continues the saga begun with the Nebula and BSFA-finalist novel, The Inn at the Amethyst Lantern. Join this unforgettable adventure where light battles darkness and friends navigate mysteries beneath the stars.
Summoned by the mysterious Gallant Twilight Society-a network of heroic animals-Gen journeys beneath the waves into hidden lairs pulsing with bioluminescent secrets. With her loyal team, the Fireflies, she confronts lost legacies, mutated monsters, and shadowy figures from the past.
When a vibrant yet unsettling new apothecary arrives, secrets multiply and trust frays. And as danger closes in, Gen learns the true weight of leadership and the strength of friendship.
Filled with wonder, bravery, and the luminous bonds of community, The Secret of the Sapphire Sentinel continues the saga begun with the Nebula and BSFA-finalist novel, The Inn at the Amethyst Lantern. Join this unforgettable adventure where light battles darkness and friends navigate mysteries beneath the stars.
352 pages, Paperback
Published October 3, 2025
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2 people want to read
About the author
J. Dianne Dotson
9 books118 followersFollow me at Jendia Gammon. J. Dianne Dotson, who also writes as Jendia Gammon (Atacama, 2025, from Sley House Publishing; Doomflower, 2025, from Encyclopocalypse Publications), is the Nebula and BSFA finalist author of The Shadow Galaxy: A Collection of Short Stories and Poetry (Trepidatio Publishing), the four-book space opera series The Questrison Saga© (Heliopause; Ephemeris; Accretion; and Luminiferous), and The Inn at the Amethyst Lantern (Android Press). She is also a science writer and artist.
Visit her website at www.jendiagammon.com
Visit her website at www.jendiagammon.com
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Displaying 1 - 2 of 2 reviews
October 13, 2025
I received a free advance reader copy/uncorrected proof of The Secret of the Sapphire Sentinel from the author. I very much enjoyed the first book in this lunarpunk sci-fantasy series—The Inn at the Amethyst Lantern and its wildly imaginative night-living world, so I was very grateful when Jendia reached out to offer an ARC of the sequel and I jumped in straightaway. Serving up another helping of immaculate lunarpunk vibes and spirited adventure. I really like the cover on this one even better than the first book, too. Stunning work.
A solid and enjoyable sequel, The Secret of the Sapphire Sentinel is a fun YA romp through a beautifully immersive post-apocalyptic lunarpunk world. We pick back up with Gen Lightworth mere weeks after the events of the previous book when the town of Glimmerbight is trying to get back a sense of normalcy. There is work to be done at the Inn and the teens have to go back to school, but the monsters are still out there and the town’s protections are failing. Mysterious new arrivals in town stir Gen and the Fireflies’ suspicions.
The world of the ancients expands as Gen and her friends try to find a solution for the failing power source in the Inn. I particularly liked Gen’s growth throughout the book, and her interactions with Styx. As much as she learned in the previous book, she still gets things wrong and jumps to conclusions. But in the process she learns how to be a better leader and use her friends’ strengths more effectively. The supporting cast was just as vibrant and fun as the first book. I wasn’t too sure of the subplot with Jas and his affliction, however, as while it hung over the characters, nothing much came of it beyond Gen checking his dosimeter. I really enjoyed the talking animals of the Gallant Twilight Society, though—it would be cool to see more of them.
The action overall was great, and I could follow what was happening easily. The monsters were creepy and lightly unsettling. And I loved seeing more of the Inn at the Amethyst Lantern. The final battle was bombastic and brought all the characters into play in interesting ways. But I think this is where I’m not quite the target audience as I could feel the story pulling its punches a bit, probably for age considerations, and it reduced the tension for me.
Overall, good fun and I’d still recommend it for all the same reasons I recommended the first book: For anyone looking for climate change sci-fantasy in the YA space, or just generally for a whimsical fantasy adventure. I hear there’s a prequel in the works, so I’m definitely going to keep an eye out for that.
A solid and enjoyable sequel, The Secret of the Sapphire Sentinel is a fun YA romp through a beautifully immersive post-apocalyptic lunarpunk world. We pick back up with Gen Lightworth mere weeks after the events of the previous book when the town of Glimmerbight is trying to get back a sense of normalcy. There is work to be done at the Inn and the teens have to go back to school, but the monsters are still out there and the town’s protections are failing. Mysterious new arrivals in town stir Gen and the Fireflies’ suspicions.
The world of the ancients expands as Gen and her friends try to find a solution for the failing power source in the Inn. I particularly liked Gen’s growth throughout the book, and her interactions with Styx. As much as she learned in the previous book, she still gets things wrong and jumps to conclusions. But in the process she learns how to be a better leader and use her friends’ strengths more effectively. The supporting cast was just as vibrant and fun as the first book. I wasn’t too sure of the subplot with Jas and his affliction, however, as while it hung over the characters, nothing much came of it beyond Gen checking his dosimeter. I really enjoyed the talking animals of the Gallant Twilight Society, though—it would be cool to see more of them.
The action overall was great, and I could follow what was happening easily. The monsters were creepy and lightly unsettling. And I loved seeing more of the Inn at the Amethyst Lantern. The final battle was bombastic and brought all the characters into play in interesting ways. But I think this is where I’m not quite the target audience as I could feel the story pulling its punches a bit, probably for age considerations, and it reduced the tension for me.
Overall, good fun and I’d still recommend it for all the same reasons I recommended the first book: For anyone looking for climate change sci-fantasy in the YA space, or just generally for a whimsical fantasy adventure. I hear there’s a prequel in the works, so I’m definitely going to keep an eye out for that.
September 27, 2025
Gen is once again summoned to rise to the occasion when danger lies ahead. With her Firefly friends, and some new, not-so-human allies, she has to figure out who can be trusted and who might be a threat. I’d recommend starting with The Inn at Amethyst Lantern before diving into this one, so you can really get to know the world and characters. Like the first book, this story is set in a future where Night Living is the norm and daylight is far too dangerous. And that’s only one of the dangers waiting ahead.
Displaying 1 - 2 of 2 reviews