The Iron Trial, written by Holly Black and Cassandra Clare and published September 9, 2014, by Scholastic Corporation, is the first book in The Magisterium Series.

Call participates in a test to see whether he has sufficient magic to attend the Magisterium and train to be a mage using the four elements: fire, water, air, and earth.

[3] Kirkus Reviews called the book "[a] promising beginning to a complex exploration of good and evil, as well as friendship’s loyalty.

"[3] Maggie Reagan, writing on behalf of Booklist, provided a mixed review, stating, "Expectations are bound to be high for this powerhouse duo’s first co-written effort, and although it doesn’t quite live up to the authors’ respective works...and there are several missed opportunities, the end offers a few intriguing twists and perspectives that hint at what's to come in the next installments.

"[4] In 2016, the American Library Association named The Iron Trial one of their top ten Quick Picks for Reluctant Young Adult Readers.