Stone Cold Fox

Dark Billionaires #4

by Stevie Sparks

A fatal mistake. A desperate escape. A violent protector.

When she came to me for help, bloodied and trembling, I should have known danger was on her heels.

She’d seen something she shouldn’t have. It had been an innocent mistake, but then everything about her was innocent. Penny’s path had never left the straight and narrow. Mine was littered with violence and murder, and she hated me for it.

I’m reluctant to help given the bad blood between us. I’m her enemy, not her saviour. But in the end I bring her with me—and the longer we travel for, the more I realise how alone she is in this world. How vulnerable. How…beautiful.

I don’t know when I started to like her. I don’t know when this became personal. I don’t know when she became this obsession, but I’m powerless to stop it now.

All I know is they’re coming for her, and anyone who tries to take her from me will die screaming.

💚 Enemies to lovers
✨ Forced proximity
💚 Road trip
✨ Innocent heroine × dangerous hero
💚 One bed
✨ Slow burn

Genres: Dark Romance, Enemies To Lovers

206 pages, Kindle Edition

Published April 30, 2026

About the author

Stevie Sparks is a British author and long-time copy editor from Windsor, England (where Windsor Castle is).

She suffers from a terrible medical condition that has left her incapable of reading books without smut. She also has multiple sclerosis. When it comes to books, she prefers the phrase 'full steam ahead.'

Stevie writes both contemporary and historical romance.

Reviews

[Gloria · Rating 2 out of 5]

The main characters: the author gave both of them heavy baggage to carry, and delved no further.

The romance: actually had some cute moments and chemistry up until a steamy Monopoly game and then it turned into a rundown of sexual positions.

The element of danger: had potential but the author barely paid attention to it, other than as a way to throw the main characters together and insert some violence at the end in order to label it “dark.” Perfunctory is what I’d call it. And, of course, it relied on the FMC being stupid enough to walk right into a trap that had “trap” stamped in its forehead.

[Michelle Frater · Rating 4 out of 5]

Honestly, I’m endlessly baffled by how these so-called criminal masterminds manage to function when they treat incriminating evidence like loose change, just scattered around for anyone to find it. Unfortunately for Penny, she’s the unlucky one who does exactly that, discovering a damning video while working late one night… and instantly becomes a target. This story doesn’t ease you in, it detonates. Penny barely escapes an attempt on her life, only to dive headfirst into the car of the one man she has never trusted. To her, Rhys Stone is a killer. Full stop. Also? An infuriating, stubborn, walking headache. So, when he brushes off her claims as paranoia, you can’t exactly blame her for wanting to scream. That is, until reality quite literally moves in the shadows behind her curtain of her apartment and suddenly, disbelief is no longer an option. What follows is chaotic, high-stakes and wildly entertaining, when Rhys, perhaps surprising himself most of all, decides to help her. Their trip to Villa Scilly, which quickly becomes the setting for one of the craziest and funniest forced-proximity scenarios I’ve read in ages. One of my favorite hilarious moments was when Rhys bought Penny the bakery-themed wardrobe including Crocs adorned with sausage rolls. Absolutely classic. But beneath the humor, something deeper starts to unfold as Penny and Rhys begin to see each other more clearly and what they find doesn’t quite match the stories they’d been telling themselves. Vulnerability creeps in through the cracks. I loved how Penny felt safe with Rhys and how he found himself wanting to protect her. Rhys’s subsequent hemiplegic migraine and Penny’s later panic attack reveal stronger feelings than they’re willing to admit. The tension between them builds just as relentlessly as the danger closing in. But, make no mistake, this isn’t all about the banter and growing heat between them. There’s real darkness here. The threat is constant, the action sharp and often brutal, and the sense of pursuit never lets up. By the time you reach the finale, it’s a full-throttle, edge-of-your-seat ride that doesn’t pull its punches. In short: chaos, chemistry, and just enough craziness to keep you grinning through the tension.
I received a free copy of this book and am voluntarily leaving a review.

[Malini · Rating 5 out of 5]

It's him by MeemsAngel82

The one man she thought she hated and the one who certainly bothered her, drove her crazy and didn't want to acknowledge. That man. He's the savior for her and as they begin to truly know one another, there is more danger and revelations she and he both are shocked by.

He saved her and continued to do so, his real story and hers making them rethink their stance on one another.

They were attracted and she was not happy with him. The irony that he is at the right time and place isn't lost on them. They have quite an adventure dodging danger and getting to see intimate details of the other's life. Them bantering and having an unusual adventure got her to loosen up and him to see a side of her that he couldn't walk away from. She felt it and I'm happy they didn't dodge the issue. They had a crazy journey and though the set up for him in this one-was he with a couple?!-wasn't my cup of tea, he proved himself to her. He had his own charm and was the right person to comfort her and in turn her instincts to nurture came out over him and it was sweet. They make an interesting couple and this was entertaining!

I received a free copy of this book and am voluntarily leaving a review.

[Johanna · Rating 5 out of 5]

Book 4 of Dark Billionaires. Can be read as a standalone.

'I don’t know when she became this obsession, but I’m powerless to stop it now.
All I know is they’re coming for her, and anyone who tries to take her from me will die screaming.'

The characters were very complex and compelling and complicated and perfectly steamy together. Plot was intriguing and intense and well paced. World building was excellent and solidly drawn. Another great addition to the series. Thoroughly enjoyed and highly recommend!

Grab a copy, kick back and enjoy!.

I received a free copy of this book and am voluntarily leaving a review.

[SusanT62 · Rating 4 out of 5]

Rhys and Penny embark on a journey that brings them together permanently!

This was a suspenseful and action-filled erotic story. The lead couple are great together and their chemistry is apparent from the get go. You will enjoy following them as they deal with issues. I really loved the epilogue.

This is labeled as a “dark romance” so please check the triggers before reading. I did not find it excessively “dark” but this is strictly my opinion.

I received a free copy of this book and am voluntarily leaving a review.

[Amber Novak · Rating 4 out of 5]

This is book 4 in the Dark Billionaires series and follows Penny as she tries to outrun the people after her when she saw something she shouldn't have, and Rhys, the man she midjudged who vows to keep her safe. As they work to stay on step ahead of danger, the attraction between them grows stronger until they can't fight it anymore. Just the right blend of action, danger, a little mystery, plenty of love, and a HEA make this a great part of the series.

I received a free copy of this book and am voluntarily leaving a review.

[Alexandra Rose · Rating 3 out of 5]

✨Summary✨
Rating: ⭐️⭐️⭐️.5
Spice: 🌶️🌶️🌶️.5
HEA: Yes, no 3rd act breakup
POV: Dual
Tropes: Billionaire, Enemies to Lovers, Romantic Suspense, Business Associates, He Saves Her, Migraine Rep, He Falls First

Rhys and Penny have known each other for years, and their relationship has always been tense. Penny can’t stand him, convinced he’s a rich criminal with no moral compass, while Rhys thinks she’s rigid and snobby and purposely enjoys getting under her skin. But when Penny comes across something she was never supposed to see, her life is suddenly in danger and she’s forced to rely on Rhys for protection. As they spend more time together, they begin to realize the other isn’t who they thought they were, and there’s far more beneath the surface for both of them. Soon their relationship becomes something more as they fight not only for their lives, but for a future together.

I really enjoyed the last book in the series and was excited to get to know Rhys better. Unfortunately, this one fell a little flat for me. The story felt rushed at times, and there were several plot holes and inconsistencies that pulled me out of the story. I liked Rhys and Penny together and thought they had good chemistry, but I never felt like I got enough time with them to fully connect to their relationship. The previous books in the series were over 300 pages while this one was closer to 200, and I really think this story would have benefited from more development.

[Emma Lee · Rating 4 out of 5]

I don’t often read contemporary but always make an exception for this author. A pining hero in some respects a lady who knows her own mind but is willing to change her opinion. Just a wonderful steamy read. Didn’t let me down.

I received a free copy of this book and am voluntarily leaving a review.

[Leanne Bryson · Rating 4 out of 5]

Rhys and Penny embark on a journey that binds them together permanently!
This is a suspenseful, action-packed erotic romance with fantastic chemistry between the leads from the very beginning. I loved following their story and especially enjoyed the epilogue.

I received a free copy of this book and am voluntarily leaving a review.

[JM G · Rating 5 out of 5]

I really enjoyed reading Stone Cold Fox. The storyline pulls you in from the start and keeps your interest all the way through. Penny & Rhys have a great connection and you can feel it as you read their story. I hope you enjoy it as much as I did. I look forward to reading more by this author.

I received a free copy of this book and am voluntarily leaving a review.

[Lauren Valcourt · Rating 4 out of 5]

Rhys and Penny are an unlikely duo that fall for each other hard through a series of scary events. This book had just the right amount of suspense and the right level of spice. I only wish the ending was a little longer.

[Jenni · Rating 5 out of 5]

When Pennys lofe is in danger theres only one person who can protect her even if she hates him, Rhys, these two couldnt be more opposite yet the longer they are together the sparks fly but can he keep her safe? Well written fast paced dark themes steamy enemies to lovers

[Happyscribe · Rating 4 out of 5]

Fast paced, twists and misadventures but didn't send my pulse into overdrive. But this author is still a hot fave of mine as they really know how to craft tension!.

I received a free copy of this book and am voluntarily leaving a review.

[Narelle · Rating 4 out of 5]

Penny comes to Rhys when she needs help. A steamy dark read as these enemies to lovers get to know each other better, realising how wrong they were about the other.

I received a free copy of this book and am voluntarily leaving a review.