‘Radiant Sin’ by Katee Robert: Apollo and Cassandra’s slow burn romance is scorching hot

This Radiant Sin book review is a spoiler-free look at the fourth book in the Dark Olympus series—and it might be the hottest one yet.

Of course, calling it the hottest one yet is highly subjective, but I couldn’t help a reference to the sun god himself. Truth be told, Radiant Sin might actually be my favorite book in the series. I’ve loved them all so far, for vastly different reasons, but this one hit on so many of my favorites tropes and dynamics that I’d be lying to myself if I said it wasn’t right there at the top.

Related: ‘Wicked Beauty’ by Katee Robert: The story Helen deserved all along

It should come as no surprise that this book features a grumpy X sunshine dynamic between Apollo (obviously the sunshine) and Cassandra (a perfect grumpy heroine), but it also has a little bit of a forbidden romance (Apollo is Cassandra’s boss) and a fake dating scenario. Aside from that, you can also expect to see the “there’s only one bed trope,” a smattering of “good girl” praise, and a perfectly soft dom who knows how to straddle that line between firm and affectionate.

The Thirteen certainly have a reputation for ruthlessness, but all things considered, Apollo might be the best of them. Sure, he’s the spymaster, which means he deals in secrets and knows how to manipulate people, but he might be a little too honest to do that role justice. It’s served him well so far, but you also can’t deny that it’s a weakness in the eyes of those in the inner circle.

It’s easy to fall in love with Apollo. As a member of the Thirteen, he’s probably done the unforgiveable on occasion, but his hands are cleaner than most. He longs to care for Cassandra, to show her that he can be gentle with her heart—but don’t mistake him for a pushover. He’s a practiced dominant, as good at aftercare as he is at commanding a sub to serve his needs. That ability to swing between roles isn’t always easy, but Apollo does it effortlessly. Don’t get me wrong—I love a brooding hero, but I can’t deny that Apollo was a breath of fresh air.

The other half of this relationship is centered on Cassandra. I love the grump X sunshine trope, and it’s even more fun when the grumpy character is a woman. Cassandra has a sharp tongue, and she rarely holds back from saying what’s on her mind. Her disdain for the Thirteen is well-known, and all she can think about is getting out of Olympus and away from her tragic past.

I say that’s all she can think about, but this Radiant Sin book review would be a lie if I didn’t tell you she can’t stop thinking about Apollo, either. She might hate the Thirteen, but after five years of working for him, she’s come to realize that Apollo is a genuinely good person. It doesn’t stop her from wanting to leave Olympus, but it does make her time there a little easier.

There’s so much I love about Cassandra, from her sharp wit to her razorblade tongue to her complex character. She’s flawed and jaded and kind of a bitch sometimes, but she’s real. Like so many of Katee Robert’s characters, she’s plus-sized and queer and so damn relatable it hurts. For years she has suffered so her sister didn’t have to, but now it’s finally her turn to shine.

radiant sin katee robert book review

What I love most about the Dark Olympus series—other than the clever way Katee inserts subtle references to the original myths—is that the story is as interesting as the spice, and Radiant Sin pushes the plot forward in leaps and bounds as Minos makes his presence known in Olympus. Joined by Pandora, Ariadne, Theseus, Icarus, and the Minotaur, the Thirteen know he’s up to something, but they can’t quite figure it out.

Luckily, Minos presents them with a perfect opportunity—a house party in which several members of the Thirteen and their loved ones are invited. Apollo is sent to spy on Minos, and he brings Cassandra along for the ride. She’s excellent at reading rooms and divining information he may have missed, so there’s no question in his mind that she’ll be an asset. As for her? Well, this provides her the opportunity to finally leave Olympus behind forever.

The only problem is that Apollo and Cassandra must pretend to be dating so her presence at the party doesn’t raise any eyebrows. It’s not hard to see where their relationship goes from here, but I wouldn’t be doing my Radiant Sin book review justice if I didn’t tell you it’s scorching hot. This was Katee Robert’s version of a slow burn, and it was worth every agonizing moment.

Minos continues to be a mystery throughout most of his book, and his parlor games feel a little bit like they belong in a game of Clue—with the requisite danger nipping at everyone’s heels. The mystery was intriguing, and I’ll admit that I wasn’t able to see the whole picture until it was revealed right before my eyes.

I promised this Radiant Sin book review wouldn’t contain any spoilers, and I’m holding myself to that, but after this book, I’m looking more closely at Hermes than ever before. She continues to be an incredibly complex character—the epitome of chaotic neutral, to be sure—and the implications of the information we learn in the final chapters blows this series wide open.

I’ll admit that I come for the spice with each and every Katee Robert book, but I stay for the intricate plot. She’s built a rich world with the Dark Olympus series, and each subsequent installment gets me more excited for the next. I was lucky enough to reveal the cover for Cruel Seduction, as well as a sneak peek at one of the chapters. Aphrodite, Hephaestus, Pandora, and Adonis will no doubt make for an interesting dynamic, and I’m just as excited to see them in action as I am to find out how Olympus will deal with the all the developments we witnessed in Radiant Sin. But how will I ever make it to the August 8, 2023 release date without spontaneously combusting? I guess only time will tell.

‘Radiant Sin’ published on February 7, 2023

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