The book follows Pierce's characters Briar Moss, Evumeimei Dingzai (nicknamed Evvy), and Rosethorn after the events of her 2001 novel Street Magic. An elite group of technicians, the Battle Magic mercenary unit specialized in upgrading and refitting military hardware. The unit was destroyed while fighting the forces of Wayne Waco on Outreach, but their development of the advanced Multi-Missile Launcher ensures that their name lives on. Battle Magic is a class of Magic Skills that emphasizes on offensive magic skills.
On their way to the first Circle temple in Gyongxi, mages Briar, Rosethorn, and Evvy pay a visit to the emperor's summer palace. Set two years before the events of THE WILL OF THE EMPRESS and MELTING STONES, this adventure reunites plant mage Briar; his mentor, Rosethorn; and his young apprentice, Evvy, who has a talent for making stones...do things. The three journey eastward to the forbidding land of Yanjing, where they discover a danger that threatens the home temple of the Living Circle religion Remedial Battle Magic is the eleventh episode in the first season of The Magicians.