Mercury Raine: The Forever Flame

Mercury Raine #4

by Sarah M. Eden

Mercury Raine left London years ago, intending to never go back. Needing to never go back. His carefully guarded past is far too easy to piece together in that city. But the lady who has claimed his heart is being held hostage there, bait intended to draw him out.

Determined to find her, Mercury takes the risk of returning to Town. Navigating the dangers that await him there will require all the stealthy survival skills he learned living on the streets of London and more than a little luck. But the peril that awaits him is far greater than anything even he could imagine.

Genres: Fiction, Fantasy, Historical Fiction, Historical, Paranormal, Historical Romance, Audiobook

98 pages, Kindle Edition

Published May 26, 2026

Reviews

[Holly (IG Hollys_Book_Musings) · Rating 5 out of 5]

"That seemed to be the theme for the night: the countless things Mercury wished he knew."

Mercury Raine book 4: The Forever Flame by Sarah M Eden

Oh my goodness, I loved this newest book in the Mercury Raine series! And I cannot wait for book 5!

I love Mercury Raine's character and how a little more is unraveled about his past. Sarah definitely keeps you guessing throughout this book and this series.

There is a bit of longing and definite sparks of romance/attraction. I cannot wait to see more of Mercury and Tacey's chemistry.

Again, I love the length of each of these stories. The intrigue and suspense just keeps building. Definitely recommend this next installment in the Mercury Raine series.

I had the opportunity to listen to a copy of the audio and again it was just as amazing as the first 3 on audio in story and narration! Highly recommend getting the audio for this series!

Favorite Parts:
Going to London
Changing identities
Intrigue
Hand touches
Sneaking around
Rescue mission

Content Guide:
Language: none
Sexual Content: Clean-feelings of attraction, hand touch
Violence/gore: Mild-kidnapping, abuse (alluded to), a ghost can decapitate his own head (no gore described)Substance Use: Mild-some mild drinking conducive to time period
Prejudices: against orphans
Religious Content: none
Other: orphanage, abuse (alluded to), ghosts, special ability

Book Info:
Series: Mercury Raine 4
Genre: Historical Romance; Regency with a touch of magic
Romance Level: Clean
Release Date: May 26, 2026
Publisher: Pineway
POV: single third person

Thank you to the Author for the review copy. All thoughts are my own.

[Kristalyne, love.lovely.books · Rating 5 out of 5]

This book is so exciting. This story is getting more intense, and there is looming danger, suspense, and secrets to discover!!!!

I really love Mercury Raine, and getting more of his backstory was all that I’ve been hoping for!!!! I really enjoyed getting to know him better! I absolutely loved all the secrets that are revealed. They had me completely hooked to this story!

I love Mercury and Tacey, and I also love the ghosts! I love how they all worked together to figure things out! They are so clever, and this story is very creative and fun.

The danger and suspense in this novella had me on the edge of my seat, and that cliffhanger left me wanting more! More of these characters and this wonderful story!!!

This story is intriguing, it’s suspenseful, it’s exciting, it’s so unique, clever, and I really enjoyed reading it.

I cannot wait for the next installment of Mercury Raine! It’s going to be so soo goooooood!!!
.
.
.
Content: danger, suspense, trauma in the past

This is book 4 in this novella series!

[Anna Cloninger · Rating 4 out of 5]

These books absolutely need to be longer. You barely get anything out of such a short book!! When the series is finally done, I would appreciate a volume containing all the individual books bound together.

At any rate, I loved it regardless. Yay for Mercury Raine!! Huzzah for rescues!! Hooray for London!!

[Mara · Rating 5 out of 5]

Another captivating, suspenseful installment that I couldn’t put down! This series continues to pull me deeper into this world! These novellas are the perfect length for an escape read—quick enough to devour in a sitting but packed with mystery, danger, and heart.

Mercury hasn’t returned to London since leaving years ago, determined to keep his past buried. But when Tacey is kidnapped and taken there, he has no choice but to go to London with all his ghostly attachments. I loved watching Mercury navigate the streets of London using the survival instincts he learned long ago; it added so much tension to the story.

We get a few hints about who is targeting him and why, but not nearly enough answers yet! The danger feels real no matter where they turn—whether staying in London or returning to Aventine Manor. This installment left me desperate for the next book because I NEED answers.

If you’re planning to start this series, definitely read it in order since each novella builds directly on the larger story and mystery.

[Angela (justwant_2read) · Rating 5 out of 5]

Oh my goodness, I really do think this is one of my favorite Audiobook series!!! (This is a review for an advance listening copy I received. All opinions are freely given and are my own.)
I am OBSESSED!! @jakestormoen is one of the best voice actors I have ever heard. Seriously. I don’t know how he keeps track of the many, many voices that he does, but he does it so well. And they are all so memorable, and intriguing.
Then you have the storyline, that just keeps reeling us in and leaves us hanging in anticipation for the next one 😂 Every time I finish, I wonder how on earth I will wait for the next one!! @sarah_m_eden has seriously found her next level of genius for this series. It is fantastic, and I am DYING to get the next one!!!!
An absolutely must listen (the book is so good, but you have to listen to Jake read it!!

[Katie (hiding in the pages) · Rating 5 out of 5]

Sarah Eden has been a very favorite author for years and her Mercury Raine series isn’t like any other. Told in a serial-style format, the layers peel away with every installment.

Mercury Raine is a ghost broker enshrouded in mystery. When his protege and love interest is held as bait to lure him out, he must return. The danger that lurks, along with the plethora of ghosts who are bound to him, bewitch me more with every addition to this series.

I was lucky enough to listen to this one and the narrator does an impressive job with the narration, bringing each character to life in such vivid ways–it was like a movie in my mind.

Easy to binge in a sitting, Each story builds upon the previous one, so I would definitely read these in order. Mercury Raine has secrets and I can’t wait to discover them. Eden’s writing keeps me fully invested and I’m already dying for more.

*I received a complimentary copy. All thoughts and opinions expressed are my own and were voluntarily given.*

[Korbie Harrison · Rating 5 out of 5]

This series is the perfect escape! It’s a delightfully unique premise, and the characters are just charming. Mercury and Tacey are both deeply interesting people, and each likeable in their own right. I do, however, think I might enjoy the ghosts even more, especially Zizzy and Baby Blue!

The novella format is precisely the right fit - the length is long enough to cover each new development of the plot well, but short enough to be read within a sitting or two! Reading each installment feels much like what I imagine reading the serial novels (like how Dickens published!) and it is an absolutely perfect delivery.

This is the first one of the series I’ve read as an ebook (I listened to the audiobooks for the others!) and I’m happy to report that the series in delightful whether you’re reading with your eyes or your ears! I’ve enjoyed experiencing the series via both formats and happily recommend either!

Thank you to the author for the ARC; all opinions are my own!

[Erika Tarpenning · Rating 5 out of 5]

*excited squeal* The adventure continues! Someone is after Mercury and knows at least some of his secrets from his past. It puts Tacey and his ghosts in danger but if anyone can solve it, it’s Mercury Raine! It’s amazing how Sarah Eden can pack adventure, mystery, and build characters in such a short novella. Some things are satisfied, but other questions are raised!

[Marsha · Rating 4 out of 5]

This is a great series but I wish I would have known there were SIX books in the series as I would have waited to start reading it until they all came out. I don’t like waiting when the suspense builds but the book ends without full resolution. The next book is supposed to be out in September 2026 and the last book in January 2027. I may wait for the last book and then reread the first four before reading the last two. These books are short, more like episodes or novellas. I love that the series is so different from anything I have ever read and certainly different from this authors usual books.

[Caroline · Rating 5 out of 5]

Quick read that left us on another cliff hanger! Hurry up September so we can see what happens next!

[Laramee · Rating 5 out of 5]

Another fantastic installment in the Mercury Raine series!

[Jessica Roberts · Rating 5 out of 5]

The story is getting so good! I love all the ghosts and their loyalty to Mercury and even Tacey. And that they were so determined to help in this book. Can't wait until the next one comes out!

[Shayla Riley · Rating 5 out of 5]

Mercury Raine: The Forever Flame
(Mercury Raine Series Book 4)
by: @sarah_m_eden

••I give 5 stars!⭐️⭐️⭐️⭐️⭐️

~Mercury Raine left London years ago, intending to never go back. Needing to never go back. His carefully guarded past is far too easy to piece together in that city. But the lady who has claimed his heart is being held hostage there, bait intended to draw him out.
Determined to find her, Mercury takes the risk of returning to Town...

“we will meet again, Mercury Raine. When we do, remember this moment.”

-Mercury Raine: The Forever Flame, is the fourth delightful installment in the thrilling captivating Mercury Raine Series. It did NOT disappoint, whatsoever! My goodness, my friends, this story is packed so full of unforeseen circumstances, stealth, espionage, a great amount of mystery, and such sweet charm! The lurking danger, and suspense, had me sitting on the edge of my seat, deliciously savoring each and every clever part that came along. I simply could not get enough of this tale and even with a cliffhanger at the end, I thoroughly enjoyed this story! Now you should know that this series is definitely a must read and is best read in order. •Do not just jump in but, start at the beginning for full enjoyment because each story is like a puzzle piece, that slowly and creatively unlocks more of the mystery and charm within. I am already anxious and thrilled to see where this series goes next! Truly, the beautiful mixture of mystery, humor, and clever ghosts have my heart. I love how book has such an immersive, imaginative, and vivid setting, where I was pleasantly and expectantly surprised along the way. I love how dear characters continue to have the ability to charm, humor, and intrigue me as well. Friends, this story and series is absolutely worth reading! Well-done, dear @sarah_m_eden 📚👌‼️💯

“I can be what I need to be whenever I need to be.”

•Content: no language, mild danger-kidnapping, a guard with a gun (never pointed at anyone), orphan/orphanage (past), some drinking.

“I would happily sleep in the servants’ quarters if it meant you would remain.”

#mercuryrainetheforeverflame
#mercyryraineseries
#sarahmeden
#allaboutthebestreads

[Jesica · Rating 5 out of 5]

“He was in danger, his life’s work under threat, his future entirely uncertain. Yet, in that moment, he felt unexpectedly content. More than content, though he couldn’t identify the primary emotion.”

I love me some ghosts and this series is just plain fun! This novella is the 4th installment in a fantastically fun series. It’s inspired by the Penny Dreadfuls… so it’s a quick release novella series where we will get shorter installments close together & the entire series will released in a period of a year. Set in Victorian England where ghosts are all the rage. Mercury Raine is the most sought after ghost broker in all the kingdom, with more ghosts than anyone knows and more secrets than one person should have. And those secrets are coming to haunt him. The last installment left us hanging so when I received an early copy of this gorgeous novella I dropped everything to see what happens next. I don’t want to say too much about this one because I don’t want to spoil anything but you just have to read this series. It’s a unique world full of interesting ghosts, intrigue, a bit of mystery & I can’t wait for the next installment. I can’t recommend this series enough but you definitely need to start at the beginning.

I already reread this story by audio. Jake Stromoen is a fantastic narrator and brings each of these characters to life with his many voices. It’s a fantastic audio & because it’s a novella it’s a short listen.

[The Sunshine Bookworm · Rating 5 out of 5]

I’M DYING FOR THE NEXT ONE!!!!!!

If you thought Mercury Raine was in danger before, wait until you find out the trouble he gets into in this latest installment of the Mercury Raine series. With the stakes higher than ever, Mercury and his ghosts flee Aventine Manor in search of a beloved friend. Although Mercury’s foes are ruthless and cunning, Mercury was raised on the streets and is no stranger to danger. But when the threat of unknown enemies seems to grow in tandem with those of his known enemies, what will Mercury do?

Clever, unexpected, mysterious, and bingeable, this book is a definite must read! I loved Mercury’s loyal entourage of ghosts and seeing them in a new and dangerous setting. I also love the super slow burn between Mercury and Tacey. By far my favorite part of the series is Mercury himself. He’s got that hard-to-create combination of flawed, resilient, goodness that makes him so easy to love.

Next book please! Oh, and I can’t wait for the audio!

[Melissa’s Bookshelf · Rating 5 out of 5]

Ahh, another exciting sequel in the Mercury Raine series! This latest clever, ghostly installment from Sarah M. Eden picks up right where the cliffhanger ending of the previous book left off. The Forever Flame kept me eagerly turning the pages as the highly anticipated search for Tacey begins. And, with more secrets revealed & a romance blooming, I’m captivated more than ever!

I love this series! When Tacey is kidnapped at the end of the previous book, I couldn’t wait to dive into The Forever Flame. Finding her isn’t going to be easy, especially with the secrets Mercury is hiding & the very real danger of someone from his past recognizing him. It also doesn’t help that he’s a ghost broker with an unusually large number of ghosts who must stay within close distance of him. I enjoyed seeing him ferret out the clues & discovering why so many ghosts are remember the past he’s kept so well hidden. I also love Tacey & her ability to keep her wits about her in the most trying of circumstances. It’s clear there’s something brewing between her & Mercury, & I can’t wait to see everything play out.

This unique premise of Regency era England combined with a creative spooky gothic paranormal element has completely captured my imagination. Add in a sweet slow burn romance & several lovable ghosts each with unique abilities & personalities & I’m hooked. With more pieces of the puzzle revealed, I’m even more invested in discovering who wants Mercury & why. And, with all the secrets unraveled in this story, I can’t wait to see a final showdown between those searching for Mercury & discovering who he really is & how he ended up in the orphanage.

Highly recommend this fun, ghostly series to fans of clean gothic romance! This clever, unique series is definitely one that needs to be read from the beginning in order to appreciate each clue & secret revealed. Can’t wait for the next book! I received an advanced copy but also borrowed in Kindle Unlimited. All opinions are my own & voluntarily provided.

[Kristi W - Book Love By Kristi · Rating 5 out of 5]

•Fortunately for them all, Mercury had never been intimidated by the impossible.•

This is the fourth novella in the Mercury Raine series. I was hooked from the first paragraph and read the entire story in one sitting. The intrigue of Mercury’s history just keeps building!

I loved seeing Mercury in London. I loved his “identities” and the way he was able to blend in. I loved how all of his ghosts worked together to uncover information and how they willing helped him with every need he had. I found the new twist on the Phantomic memories very interesting. I love how Mercury cares for his ghosts, how he asked them for help, asked them for insight, and made sure they were as “comfortable” as possible under their circumstances. I loved that he’s beginning to trust others with what he’s learning. And Tacey! The sparks are beginning to fly. I loved their honest conversations and how a single hand touch could make such a difference for Mercury. I am so excited to see where this story goes next, for Mercury and Tacey but even more to see the puzzle of Mercury become even more clear.

A few more quotes:
“I am more than ‘Mercury Raine of Aventine Manor.’ I can be what I need to be whenever I need to be.”

“Still as full of swagger as ever, I see.” “When one has earned swagger, one really ought to use it.”

•He’d gone his whole life without losing even the tiniest bit of his heart. Now, someone had claimed a corner of it, and she likely was discovering she didn’t want it.•

[Kass Rob · Rating 5 out of 5]

I swear these little Mercury Raine books somehow keep getting more addictive with every installment! This next book gave just enough answers to keep me satisfied while also dropping new mysteries that immediately made me desperate for the next book! One of my favorite things about this series is that with each story we learn just a little bit more about Mercury! Tiny pieces of his past, his secrets, and what makes him who he is! It totally makes the whole series feel like one giant puzzle slowly coming together!

I loved this book especially, because of the strengthening connection between Mercury and Tacey! And the risk Mercury is willing to take to ensure her safety! The mix of mystery, humor, and ghosts, keeps these stories feeling fresh even though they’re short reads!
Every time I finish one, I immediately want the next one in my hands because I’m definitely dying to know what comes next!

Thank you so much to the author and publisher for an advanced copy of this book. All thoughts are my own.

[Mandy · Rating 5 out of 5]

This series is so good; I’m hooked more and more with each installment and The Forever Flame has me even more intrigued and invested than ever before.
Mercury Raine risks his own secrets and safety to go to London in order to rescue Tacey, the lady who has slowly captured his heart. With his band of ghosts, he works to rescue Tacey, all while his own enemies are closing in. The secrets and reveals in this book!!! I’m on the edge of my seat for the next book and so anxious to see what happens next, especially knowing what I know now as the reader.
Jake Stormoen is the best narrator for this series and honestly, the audio version is my preference for reading them. They are so fun and it’s like listening to a campfire story which I am here for. I highly recommend this book!
I was gifted a copy of the audio book version. All thoughts and opinions are my own.

[Cher · Rating 5 out of 5]

Ah! Each installment in this series triples the tension and heightens the suspense! The pacing is PERFECT with snippets of the truth coming out that just make you hungrier for more.

I loved the plot twists and developments in the forever flame and just want to fast forward to the next release! So many fun things come to light in this book—specifically about Mercury Raine. You’ll be endlessly curious about him and his life and how things are going to pan out! I'm saying very little about specific events and scenes because I don't want to spoil anything for readers.

I’m obsessed with this entire series. If you’ve even slightly considered reading them, just pick up the first one and you won’t turn back! You’ll wonder why you didn’t pick it up sooner. So SO good and original!

I was gifted an eARC but a positive review was not required.

[Cathy · Rating 5 out of 5]

I have to say Jake Stormoen does such a great job narrating these books. I love the way he does the voices for the different ghosts and other characters. He makes these books even more fun than the already are.

This book finds Mercury Raine and all of his ghosts heading to London. They must find Tacey before it's too late. I love the way Mercury interacts with his ghosts. You would think that he wouldn't care about their feelings on things, but he's a good kind of chap, and he does. He has a lot of things he's trying to figure out. Where Tacey is, why she was taken, and who is after him.

This whole series is done in the style of a Penny Dreadful, so it's got cliffhanger endings. So just know that going into reading or listening to them.

I love that these are quick reads or listens. I didn't want to stop listening to this one. And I can't wait to see how the story will end!

[Shauna · Rating 5 out of 5]

The Brief: Tacey is missing and nothing will stop Mercury from finding her.

The Debrief: This is like an episodic series that should be read in order, but if you want to jump in here and listen to Jake read to you then by all means…you’re in for a treat. He does SUCH an AMAZING job keeping keeping track of everyone. Secrets unfold in the story, but more need to be discovered. Just so good! This quirky found family is sweet and loyal to each other creating a whimsical space that @sarah_m_eden brings together wonderfully.

Yes, they are ghosts, but not creepy scary ones. I still adore Baby Blue. And I’m all in with these characters! I need more!

The Rhyme: London holds nothing for Mercury except secrets and pain. When Tacey is taken by bad guys can he rescue her and keep the truth of Mercury Raine?

[Jami Pruitt (My.lovely_readingcorner) · Rating 5 out of 5]

This is another great installment in the Mercury Raine series! I loved the mystery of trying to save Tacey and the myself of Mercury Raine himself. Learning more about the ghosts in Mercury Raine's life was also quite enjoyable.

This is the fourth book in the Mercury Raine series. It is a quick read, but should definitely be read in order.

Thanks to the author for the advanced copy. All opinions are my own.

[Nashellej · Rating 5 out of 5]

Ooh! More of Mercury’s backstory! And more ghosts! This series has captured me and this very exciting installment kept me on the edge of my seat the whole time. My only complaint is that I read it too quickly.

[Catherine · Rating 4 out of 5]

Another great installment of this ghost broker series. I love that these can be read so quickly, but then we are stuck in limbo until the next one comes out! I am looking forward to reading the last two novellas and seeing how it all comes together.

[Catherine · Rating 5 out of 5]

such a page turner!!

I couldn’t wait to turn each page. I’m trying in my head to see how the plot will play out. Having to wait til September for the next book is going to be a tough one. There again something to look forward to. Thank you Sarah

[Aj · Rating 4 out of 5]

A wonderful read and everything is getting closer even Mercury and Tacey. Secrets are unravelling and danger is lurking in the shadows. Another gem of a story. Looking forward to the next instalment.

[Shauna · Rating 5 out of 5]

I love this series! It is so fun. I love the ghost trading and learning about all of the ghosts. Sarah M Eden is a master storyteller. This book has romance, ghosts, and so many mysteries! Love love love!

[jennie.and.books · Rating 4 out of 5]

EACH BOOK GETS ME MORE AND MORE OBSESSED with these characters and this story! So much in this book and I'm so excited to see what comes next!

[Alif · Rating 3 out of 5]

another cliffhanger! 🫨
loving this series and found-family trope soooo much!