Three books are set in the Four Kingdoms: LETHAL CURSE, THE LORD OF THE CLANS and BLADE HEART. Although they can all be read as stand alone, Lethal Curse takes place 150 years before The Lord of the Clans and Blade Heart.
LETHAL CURSE: Her name is Anya and her life is about to change. The stranger who shows up at the farm to take her away is the ugliest woman she’s ever seen. Too tall, too strong, too rough. Yet that person knows secrets that must be shattered. As they travel across the Four Kingdoms to reach the city of Kings, the strange woman starts revealing disturbing truths. Anya has been cursed and as long as the enchantment lasts, she cannot see or be seen by any of the people called men. Except one. And that man is the only being in the whole world with the power to break the magic spell. Amazon Smashwords
THE LORD OF THE CLANS: Captured by a rival clan, Ariana is chained to a wall and about to be tortured. The Four Kingdoms aren’t safe anymore. As if crossing dangerous territories wasn’t bad enough, she is now trapped in a cave with her jailers. But they have it all wrong. She isn’t a spy and the legendary Lord of the Clans will believe her or execute her. He’s huge, he’s powerful and he has the power of life and death over all the tribes. But maybe she has it all wrong. Amazon
BLADE HEART: New York is Cara’s city—until one sunny afternoon when she wakes up in a beautiful meadow beside a complete stranger who seems to know all about her. If she wants to find her way back home she must stay with him. Obnoxious as he appears, she has to turn to him for protection when confronted with enemies she never knew she had. These enemies know of an ancient prophecy. They believe she’s the only one who can change it and they will do anything to stop her. As she tries to outwit and outrun them, her heart starts to beat for the stranger. Only to discover that his heart is dead. Amazon Barnes&Noble