He was kissing her with a fury that threatened to devour her. She needed this. Needed the wrath and the desire. One last time.

Gwen is a prisoner of the man she loves...

In the battle for Avalon, she sided with Mordred's enemies and allowed the demon Grinn to grow more powerful than ever.

Passion still burns fiercely between Mordred and Gwen. But the dark prince crushes his emotions and tells Gwen that he is sending her home. That she will never see Avalon-or him-again.

But Avalon has ideas of its own. The magic of the island draws Gwen back and gifts her with stunning new abilities.

Gwen has one last chance to save the island from a devastating war that would destroy everything-and everyone-she has come to love. But can she tame Mordred's rage and pride? And can a demon ever be trusted?

Continuing a heart-racing series of dark romance and seductive villains that's perfect for fans of Sarah J. Maas, Elise Kova and Danielle L. Jensen, To Break a Dark Cage will transport you to a world of wonder and danger, and leave you breathless.

See why readers love the Iron Crystal series:

"Ahh-mazing. Utterly amazing... A magical slow burn that had me reading faster with tension growing between characters... If you love fantasy romance, surprise kiss, tension, magic, read this. I am melting with excitement for the next book." Goodreads reviewer ¿¿¿¿¿

"A slow burn story full of angst, sexual tension, and betrayal. Fast-paced and addictive, you won't be able to put it down!" Goodreads reviewer ¿¿¿¿¿

"I loved it!!! Hot and brooding and morally gray and mysterious and villainous... and so, so good in so many ways!!!!" [...] ¿¿¿¿¿

"Captivating and addicting... This book is a must-read if you like romances where enemies become lovers, baddies who are seductive, and magical, dangerous worlds." Goodreads reviewer ¿¿¿¿¿

"I absolutely LOVED this book... I would give this ten stars if I could!!! I will be recommending this to everyone." Goodreads reviewer ¿¿¿¿¿

"Kathryn Ann Kingsley is the queen of writing morally gray male love interests! And of books that you will read in one sitting. I absolutely devoured To Charm a Dark Prince." [...] ¿¿¿¿¿

"This book had me tearing through it!... Mordred. Holy hotness, Batman. I loved his character. Broody, flirty, charismatic... He lit up every scene he was in." Goodreads reviewer ¿¿¿¿¿

"I absolutely loved this! Morally gray anti-hero, slow-burn romance... Anything with a dark and broody prince steals my attention. Mordred has a great, dry sense of humour and witty banter with Gwen... I'm so excited to read the next book in this series." Coffeelitandprosecco ¿¿¿¿¿

"ACOTAR fans, you'll adore this too. It's spicy, dark, angsty, dramatic... Highly recommend." Goodreads reviewer ¿¿¿¿¿