Shadow Scale

It was released in hardcover, ebook, and audio book format on March 10, 2015.

Shadow Scale appeared on the New York Times Best Seller List for Young Adult books in its first week of eligibility.

Kirkus Reviews wrote that Hartman "continues to expand her world with enough history and detail to satisfy even the most questioning of readers, doing it all so naturally that it’s hard to believe this is fiction.

"[1] Booklist[2] and Publishers Weekly also gave Shadow Scale starred reviews, writing, "This is a worthy and wholly satisfying continuation of Seraphina’s tale.

"[3] Quill & Quire wrote, "Shadow Scale is an exceptionally written fantasy seen through the eyes of a young woman caught between two worlds.