The Carbon Effect

Mastermind Murderers #3

by Kristin Helling

Psychologist Raine Walsh is at it again. One of her clients thinks he's being stalked, but the police find no evidence. She seems to be the only one who believes there's more to his story than pure delusion.
When Raine's client is kidnapped, Detective Jonah Heely doesn't think it’s coincidence. Suspended or not, he's determined to find out why Raine herself always seems to be at the scene of the crime. Alex Wood just wants to be a normal college freshman, but he keeps dreaming that he murdered someone. When disturbing clues hint that the nightmares might be real, Alex begins to question what he might really be capable of. Raine's quest to protect those she cares about, Heely's obsession with her involvement in these crimes, and Alex's investigation into the dark corners of his own mind collide in The Carbon Effect , the third book in the Mastermind Murderers series.

186 pages, Kindle Edition

Published May 4, 2018

About the author

Kristin Helling writes stories that invite readers into small-town secrets and edge-of-your-seat suspense. She is the author of the Roastwood Hollow Cozy Mystery series, where charming coffee shops, quirky neighbors, and autumn festivals are never too far from a chilling murder. Kristin also writes thrillers and suspense novels, blending heart-pounding twists with deeply human characters who face danger, deception, and dark truths.

A lifelong booklover, Kristin grew up with a passion for storytelling and the idea that even the coziest places can hold the deepest mysteries. When she’s not writing, she owns a coffeehouse/roastery/bakery, co-owns her publishing company Wordwraith Books, is married to a photographer, and is Mama of two.

Her writing reflects her love of community, mystery, and the delicate balance of warmth and danger. Whether you prefer a comforting whodunit by the fire or a thriller that keeps you up all night, Kristin has a story to share.

📚 Series: Roastwood Hollow Cozy Mystery (In Roast Mortem, In Cold Brewed, Roastly Apparitions, with more to come!)

🔎 Genres: Cozy mystery, thrillers, suspense

☕ For fans of: Gilmore Girls, Agatha Christie, and stories that blend charm with chills

Reviews

[Teresa Collins · Rating 3 out of 5]

Having read the previous two books in these series I was expecting a little more than this one delivered. The first two books in the series at least closed out their storylines to some extent even though parts were carried over into the next book. The Carbon Effect didn't clear up anything. I finished the book with more questions that when I started. I really hate being left on a cliffhanger and this, to me was even worse. The story just ended. No resolution; no nothing. Just done. I really resent being forced to get the next book, but I'm three stories in, how can I quit now? I'm beginning to follow Detective Helley's feeling that there's something wrong with Raine and this book just pushed all of those feeling to the forefront. I'm not exactly sure why, but this story felt very disjointed. At times Marcus is hinted at having something to do with everything that's gone wrong in Raine's life and then it's Professor Jensen, when there isn't any concrete evidence to point to either one.
Also, as with the other two books, Ms Helling needs to find a proofreader, even if it's just a close friend. There are missing words, wrong words, run-on sentences, and sentences that don't make sense. Most of these are so obvious it wouldn't require an English Professor to spot them. It would make such a difference. I expected much more but was highly disappointed. I received a copy from the author but this is my own opinion

[Janette · Rating 4 out of 5]

This third installment of the Mastermind Murderers was quite entertaining and I enjoyed the Alex character, and the dog, of course! The one thing that really brought it down a star for me was how Detective Heely's character has suddenly done a 180° in regards to Raine. This doesn't really make sense and has not really been explained - even illogically. The murder case is more of a one hit wonder this time, but is still interesting. This book oddly enough feels a bit rushed to me, but I can't really explain why. Nothing seems to be properly explored before moving on to the next thing. Like it could use another 4 or 5 chapters to really flesh things out and finish them off. I can never work out if these things are done deliberately with this author, in order to represent a character's state of mind? Anyway, an excellent chapter in an altogether fun and captivating series! I received a free ARC in return for an honest review of this book.

[Claudia · Rating 4 out of 5]

Another great story in this series.

Raine is a fantastic character, and the storyline in this one is as good as it was in the previous two. What I particularly like in these books is the way they delve into the darkness of the human mind and give us a better understanding of it.

A very interesting read, totally worthy of your time.