A summer in isolation in Umbrum Hall has all of Mary's class frustrated. The students and instructors are trying to make the best of it, but it's not easy restraining hundreds of magically trained Potentials and Cadets.

Mary Quirk still hasn't gotten over seeing a world destroyed when Umbrum's fellow school of El Paso Cerrado collapsed, Now months later, some of the Paso students are returning to see if anything has survived. Mary would love to go herself, but it's not her school, and therefore, not her business.

Until something goes wrong, and then it's left to others to fix it. Mary and her class come up with a risky plan, but saving the others means putting their own futures on the line. Are Mary and her friends ready to take that leap into the unknown?