The Lost Cause

Green Ember Lost Tales Trilogy #3

by S.D. Smith

Loved ones vanish. Traitors multiply. Time is running out.

Trust is shattered and Halfwind Citadel is still reeling in the wake of a devastating betrayal. But the crystal key conspirators aren’t finished yet. And their traitorous leader still evades capture.



Heather, Picket, Jo, and Fiona run into dead ends in the search for their missing loved ones and the rogue saboteur. The loyal rabbits navigate fires, smoke, and mysterious attacks from the shadows. With every passing day, the enemies of the cause grow bolder.



When new layers of the conspiracy come to light, more bucks are drawn by the allure of the crystal key cult and many young rabbits begin to see the traitors as heroes.



Tirelessly, Picket, Jo, and Fiona push on to uncover the secret Lockhouse before their loved ones are lost forever. But deception spreads like a poison throughout the citadel.



If the conspirators succeed, the truth will be consumed by lies, the prince will fall to wicked schemes, and the hope of the Mended Wood may perish before the war against Morbin Blackhawk can be won.



With an unspeakable countdown, the Longtreaders and their loyal friends must choose courage, cunning, and truth to restore the hope they’ve been robbed of.



Set between the events of The Green Ember and Ember Falls, The Lost Cause is the thrilling conclusion to the Green Lost Tales trilogy.



Perfect for Green Ember fans, reluctant readers, and family read-alouds, this action-packed fantasy adventure blends timeless themes of truth, ingenuity, integrity, courage, loyalty, and protecting the vulnerable.



A lost tale of brave hearts in dark times—

and the steadfast fight to hold fast to truth when deception threatens everything.



Complete the Lost Tales trilogy!

The Lost Key (Green Lost Tales Book 1)
The Lost Legend (Green Lost Tales Book 2)
The Lost Cause (Green Lost Tales Book 3)


Don’t miss the original Green Ember series!

The Green Ember (Green Ember Book 1)
Ember Falls (Green Ember Book 2)
Ember Rising (Green Ember Book 3)
Ember’s End (Green Ember Book 4)

Genres: Middle Grade, Fantasy

272 pages

Published October 20, 2026

About the author

S. D. Smith is the author of The Green Ember Series, a million+ selling adventure saga featuring heroic #RabbitsWithSwords. The Green Ember spent time as the number one bestselling audiobook in the world on Audible. He is also the author of the madcap Mooses with Bazookas: And Other Stories Children Should Never Read as well as the touching throwback adventure, The Found Boys. Finally, he has co-authored two fantasy adventure novels with his son (J. C. Smith), Jack Zulu and the Waylander’s Key and Jack Zulu and the Girl with Golden Wings. Smith’s stories are captivating readers across the globe who are hungry for “new stories with an old soul.”

Though packed with old school virtue and moral imagination, Smith doesn't merely create "safe" stories, but bold, daring, truthful tales of light that help shape children who become dangerous—dangerous to the darkness.

Smith is a founder and owner of Story Warren, a publishing, events, and IP development house based in rural West Virginia. Story Warren exists to serve families as “allies in imagination.” 

S. D. Smith lives in Gran

Reviews

[The Bookworm (Jayden Mitchellson) · Rating 5 out of 5]

This was simply an amazing conclusion to the Lost Tales trilogy. It had the strongest plot and characters out of all three. This was such a satisfying ending that cleared up all the loose strands of the story! I loved Fiona and Marlan's character arcs. They might be my new favorite Green Ember characters (next to Jo Shanks).
Truly, this was amazing and I cannot wait for more Green Ember stories! They never get old, and there's always so much to love about them.

My place beside you, my blood for yours, till the Green Ember rises, or the end of the world!

[Emmy Karoline · Rating 5 out of 5]

I didn't think any book could ever be better than the Green Ember books; no other book ever written could surpass them (besides the Bible, no offense Sam). Then this book came along, proving that the only book better than the Green Ember books is a new Green Ember book (how many books could a book nook nook if a book nook could nook books?). The story was amazing, suspenseful, and insightful, bringing beloved characters to life once again in the thrilling conclusion to the Lost Tales sub-series. I guess the only book that could be better than this one is the next one...so I can't wait to find out what Sam writes next!

[Timothy Hare · Rating 5 out of 5]

An incredible read! The end left me greatly satisfied with all the mysteries and failed attempts, and the story left me with a happy, nostalgic feeling, for it has been a while since I finished a series in The Green Ember. I have missed Picket, Heather, and Jo dearly, and it was great to read them once again!

[Megan · Rating 4 out of 5]

This book was a great success! I love how S.D. Smith is able to keep writing stories with great adventures and great meaning behind those adventures. I really enjoyed how the action ramped up at the end of this one, and the subtle hints to Smalls and Heather's relationship are my favorite!

[Jonathan Hare · Rating 5 out of 5]

These Green Ember books are masterpieces for young and old alike. I haven’t read this book yet, but I am really excited to! S. D. Smith truly forges novels with love!

[Amy Russell · Rating 5 out of 5]

Another excellent adventure in the world of The Green Ember! Love the characters and especially the humor!

[Katie · Rating 2.5 out of 5]

It just wasn't really good. Not bad, of course. Just not as great as the originals

[Rey Young · Rating 5 out of 5]

This book was well-written and I really enjoyed reading it! I love all of SD Smith’s Natalia world books and this one did not disappoint.