What Happens in Onyx Storm? Full Plot Summary Explained

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February 11, 2025
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While we are all collectively recovering from the book hangover—one of the most common bookish problemsRebecca Yarros and Red Tower Books put us in with the release of Onyx Storm, life must go on dear bookworms, and we are here with a detailed summary of the third book of The Empyrean series.

For those who have not finished their re-read of Fourth Wing and Iron Flame, we got you! Cure the heartbreak with our Fourth Wing memes, refresh your memory with our book review, and memorable quotes, and finally choose a book to read after Fourth Wing.

Xaden Riorson, his intoxicating love for Violet Sorrengail, along with an exciting and unique world-building make this fantasy romance book series a must for any bookworm collection. So get on Amazon, Goodreads, or whichever alternative you prefer to start reading.


Onyx Storm

Beware bookworms, this Onyx Storm summary will be quite lengthy and will contain spoilers. 

Now lace your boots and grab your leathers, we’ve got dragons to ride! 

Onyx Storm Synopsis

Warning: There will be a lot of names you might not remember here, so we suggest you check our characters guide first!

After Xaden is revealed to have turned venin in his effort to save Violet at the end of Iron Flame, Xaden visits the imprisoned Jack Barlowe. Onyx Storm starts with Violet eavesdropping on their conversation and deciding she will find a cure for Xaden, no matter the cost. In the weeks that follow, we see the marked ones and Violet being on guard duty for Xaden at all times. Xaden remains at Basgiath War College inside the wards, to restrain himself from channeling again. 

Meanwhile, the iron squad visits Sawyer, who is adjusting to life as an amputee, while Lynx and Aaric’s failure to manifest signets raises concerns. A fresh attack on Basgiath leaves them reeling, and Violet has a chilling encounter with a silver-haired venin. After Basgiath is secured, Violet and Xaden prepare for the meeting with the Senarium—the council of all nobles of Navarre. Knowing that Andarna, Violet’s second dragon, is of the seventh dragon breed needed to power the wardstone in Aretia, Violet is sent on a quest to find the missing breed but must first fulfill her deal with Viscount Tecarus—safely deliver the fliers to Basgiath for unlimited access to his library.

Mira arrives with a new conduit for Violet and intel on tempering runes. Just as the Senarium moves to dismiss the fliers, Violet’s squad nullifies the rune blocking their channeling, salvaging the truce with Poromiel. General Aetos accuses Violet of treason, but a royal missive preemptively pardons all dragon riders who went to Aretia and reinstates Xaden as Duke of Tyrrendor.

As punishment, the Iron Squad is sent to Samara by Dain’s father. When a nearby village is attacked, they rush into battle, uncovering shocking truths: Garrick has a second signet, Theophanie—the silver-haired venin—is a Maven who wants to mentor Violet when she turns, and Andarna is an irid. Xaden later reveals that many marked ones wield two signets because their dragons chose them for a purpose. Violet begins to suspect venin can wield similarly to dragon riders.

While Xaden is away, Violet sharpens her skills and repeatedly visits Jack Barlowe, searching for answers—only to find none. A breakthrough comes in the archives when she realizes her father’s final research might be connected to the venin. She enlists Dain to steal it from his father’s office, and he delivers, leaving her with pages of secrets and a riddle to decode.

Basgiath ramps up war prep, adding a new class led by Xaden. Enter Prince Halden—Navarre’s crown prince and, as Xaden soon learns, Violet’s ex. After a brief scuffle, Halden delivers a message from Tecarus, arranging a meeting with King Courtlyn of Deverelli in exchange for a powerful relic lost in venin-infested Anca. Their conversation helps Violet crack her father’s riddle, which also leads to Deverelli.

Violet, Xaden, Mira, and an unreliable squad set off for Anca, retrieve the relic, and are immediately ambushed—losing two squad members. Enraged, Violet demands control of the mission. The new squad consists of Ridoc, Xaden, Dain, Mira, Maren, Tragen, Cat, her cousin Drake, and—unfortunately—Halden and his guard. 

In magicless Deverelli, Xaden finally finds relief, but the lack of power unsettles their dragons. While Halden meets with King Courtlyn, Violet retrieves her father’s books after a grueling test. Before they can leave, Halden is arrested, forcing Xaden to approach the king as the Duke of Tyrrendor, with Violet as his consort. Halden’s tantrum escalates into a fight, and Xaden loses control, channeling from the earth once again. Violet with the help of Tairn and Andarna, her dragons, orchestrates a ploy and secures an alliance.

Back in Basgiath, the squad prepares to continue their journey. Xaden shows up in Basgiath and Violet notices the flecks in his eyes are no longer golden but permanently amber—a direct result of his channeling. Aaric, defying orders and risking court-martial, replaces Halden as the royal representative, officially launching the quest. 

The first stop is the isle of Soneram. Dain, Xaden and Violet fight for an audience with the Queen. There are no irids on the island, but we do get a weird interaction between Violet and a priestess, revealing that Violet was almost pledged to a Goddess. Next is Hedotis, where a great surprise awaits—Xaden’s mother, Talia. Talia is now married to a member of the Hedotis Triumvirate—the local council. She tries to rekindle her relationship with her son, but Xaden wants nothing to do with her. The council tests the squad, even poisoning Garrick. Violet anticipates the betrayal and spikes their drinks first, using her father’s research to cure Garrick and secure an alliance.

The third stop is Zellyhna. The island of Zihnal, God of Luck, demands they accept whatever fate deals them. The price? Tragen’s life, who dies from an arrow to the heart. The squad travels to one of the smaller isles to burn his and his gryphon’s body. While the others search the neighboring isles, Violet and Ridoc stay back a while longer. The water and sky seem to ripple, and six giant dragons show up—the irids. 

The irids recognize Andarna but reject her for fighting in the war, branding her as a weapon. Ridoc also discovers Xaden’s venin secret and demands Violet tell the others. Their mission is officially a failure. The squad returns to Basgiath with a heartbroken Andarna and shattered hopes, only to learn Queen Maraya has been killed and Tecarus has crowned himself King of Poromiel—making Cat third in line for the throne.

Things spiral further when Lynx manifests shadows, proving magic has abandoned Xaden as this generation’s shadow wielder, and he retreats to Aretia. When the squad with Sawyer, follows for their rotation to Aretia, Violet expects a broken man but finds Xaden and Brennan still fighting for a cure.

Later that night, Xaden returns early, confessing he hasn’t channeled in 73 days—his goal is 76. They share a passionate night, only to have the same dream, revealing Violet’s second signet is inntinnsic—a dreamwalker. Before they can process it, Aretia is attacked. Violet defends the temple of Dunne, after Aaric’s suggestion, but in their efforts to repel wyvern, Tairn is injured. When Theophanie shows up, Violet defends the priestesses, but luckily when an irid arrives, firing up the Aretia wards the venin vanish.

Andarna faces a choice: stay with Violet and lose her heritage, or leave to reunite with her kind. With unbearable pain, Violet urges her to go. Broken, she spirals into grief until Mira forces her back into action. A new revelation emerges—her parents dedicated her to the Goddess Dunne to prevent her from turning venin, and there is a prophecy about her. But in reality the prophecy was about Xaden. When Xaden confesses his truth, Mira immediately moves to kill him. Violet and Brennan intervene, but Mira storms off, feeling betrayed.

Soon after, Garrick returns badly beat up with a message from Theophanie—she has Mira and wants Jack Barlowe in exchange for her. With no choice, Violet meets her, only for Theophanie to attempt to kill Jack and slit Mira’s throat. Brennan, who is a powerful mender, tries to heal her, but does not have enough power. That’s when Sloane Mairi and Dain Aetos show up with a message from Aaric—who Violet realizes is a precog. Sloane siphons Dain’s power and transfers it to Brennan, who manages to stabilize Mira. 

Violet and Bodhi face Theophanie, who is a storm wielder just like Lilith Sorrengail, Violet’s late mother. General Sorrengail was the balance to Theophanie, and now that she is gone, Violet is not sure she can stop her. Their battle is chaotic and riders are dying left and right; most notable Quinn, Imogen’s best friend. In a twist of fate, Andarna is back and helps Violet kill Theophanie with a piece of Dunne’s temple, whom Theophanie has forsaken. Just then, an onyx storm hits and Violet realizes Xaden has channeled again. 

From Xaden’s POV, we see his choosing to sacrifice his soul to save Violet and Sgaeyl. Violet whispers “I love you” down their bond before she passes out, the last thing that Xaden hears. He also reveals that Panchek has betrayed them, along with a mysterious “new brother”. The venin are defeated and Violet wakes up twelve hours later back in Aretia. She is now married to Xaden, legally making her the Duchess of Tyrrendor. But she does not remember anything after asking Imogen to wipe her memory. What a bittersweet cliffhanger, huh?

Major Themes explored in Onyx Storm

Growth and Resilience

The road from cadet to Lieutenant is hard and long in the rider’s Quadrant, and it’s even more thorny for Violet, with her weak constitution, who unlike cadets like Rhi is not meant to even be in the Quadrant. But her perseverance and will to adapt and overcome the obstacles mark her journey to growth. Her transformation from a weak cadet to a formidable leader is admirable.

Love and Sacrifice

Sacrifice is prevalent in all books of the Empyrean. From Liam to Lilith Sorrengail, riders put their lives on the line for what is right. Xaden’s love for Violet knows no bounds and despite his love for the marked ones and his Province, he puts her above all else, not hesitating to quite literally surrender his soul. 

Trust and Betrayal

The bonds between squad mates and the marked ones are a testament to the trust and loyalty that has formed between them. However, betrayal always lurks in the shadows, especially now that we have a “new brother” to worry about, not to mention Panchek and other higher-ups who are obviously double agents—our eye is on the loathsome General Aetos, just because someone can’t be that unlikeable with no good reason. 

Identity and Acceptance

Most cadets go to the Quadrant to find who they are and prove their mettle. Violet’s journey to accepting and even embracing her flaws and Xaden’s turning venin are to be commended. Xaden and the marked ones who know they can turn to ruthless killers to protect each other is also a fine example of self-acceptance.

Power and Corruption

The allure of power and unchecked ambition that leads to corruption is a repeating motif in the Empyrean series. Unlike Xaden’s anguish over turning, most venin with Jack Barlowe as the prime example, feel no remorse. Neither does King Tauri nor professors like Markham, who not only choose to ignore the refugees but have even altered history to fit their goals. 

To Sum Up

We are already on pins and needles until the release of the next book. This New York Times sensation, has earned its place in the hearts of many romantasy readers and for good reason. Fast-paced action, countless plot twists, incredible main characters and a love to die for are some of Onyx Storm’s merits. The only thing left is to read it for yourselves and tell us what you think. 

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Frequently Asked Questions (FAQs)

What does the end of Onyx Storm mean?


The end of Onyx Storm is quite cryptic. Violet’s memory loss of the last twelve hours implies that many things could have occurred in that gap. She is now married to Xaden, which means she is the Duchess and in command of Tyrrendor. It is possible that the real enemies-to-lovers tale starts now. There are also many theories about who Xaden’s “new brother” is, and if Imogen wiped Xaden’s memories as well. Stay tuned for our “Onyx Storm theories” post!

What did Violet ask Imogen to do at the end of Onyx Storm?

Imogen’s first signet—in her POV in Onyx Storm we see she has a second one as well— is the ability to alter someone’s memory. When Violet realizes she cannot remember anything from the last twelve hours, she knows Imogen is to blame. It seems that Violet asked Imogen to wipe her memory, and I guess the only way to know what happened is for Imogen to talk or for Violet to remember. 

Who turned at the end of Onyx Storm?

We wish we had the answer for you, but it is unclear who turned. Here is what we know so far. It’s someone Xaden can’t kill, he’s supposed to be dead, he can be used against Xaden, he has watched Xaden struggle for the last five months, but he is not more lethal than Xaden. There are many guesses circulating, like Brennan, Garrick, Naolin or Liam (although the last two weren’t there to see Xaden struggle). Unfortunately, we will not have our answer until the next book. Rebecca, you better hurry!

Nina Siscou
Article written by:

Christina Tsoukala

Always living in her own enchanted little world, Christina discovered the magic that can be hidden within the pages of a book when one dares to take a closer look from a tender age. An avid reader, she is constantly inspired to delve into the secrets woven between the lines and challenges herself to find her own voice amidst the chaos. She is a dedicated fan of the classics, but the supernatural creatures that have tormented readers for years are her kryptonite. The mastery it takes to infuse the author's essence, molded by the era they grew up in to their innermost desires fascinates her. Undoubtedly, putting her passion and knowledge on paper has a mesmerizing allure on her, and following the steps of so many other dreamers before her she wishes to leave her mark in the literary world. Guided by T.S Eliot’s haunting words: “I will show you fear in a handful of dust” she intends to wreak havoc in the minds of her future readers.