The desert princess : a retelling of Aladdin / (bk. 3 Return to the Four Kingdoms)
(Book)

"Cassie knows she was made for more than a life buried away in her uncle's remote forest estate. Eager to meet the great spymaster, Aurora, she jumps at the chance to travel to her distant kingdom. But meeting Aurora isn't enough -- Cassie wants to prove her worth. So when she's presented with an opportunity to gather intelligence, she acts. When her plans go awry, Cassie finds herself living on the streets in a distant city. But despite the failure that brought her there, Cassie can't afford to give up. Kingdom-shaking danger is brewing in these lands, and she may be the only one who can save the Four Kingdoms. Cassie won't let anything stand in her way -- not the biting heat of the desert, not the distracting way her heart responds to the mysterious, attractive stranger who insists on staying close, not the layers of secrets hiding beneath the surface of her new home" --Amazon.com.

015-018.