The Circle Opens is the second quartet set in the Circle Universe and written by Tamora Pierce. Each of the books follow one of the main characters from The Circle of Magic quartet. They are set in different parts of the Universe as more is explored. This quartet focuses on the four as they navigate the world as grown mages. Since they are licensed, they must take responsibility for the new mages they might discover. They also must contend with individual murderers who have different motives and weapons.
The books are targeted for an older audience than the prior quartet, and is recommended for children aged 12 to 14. As the books of the prior quartet are aimed at kids ages 9 to 11, readers are meant to literally grow up with the protagonists.
Sandrilene fa Toren opens the quartet in the first installment. She is separated from her foster-brother and sisters for the first time in her life, and is also forced to deal with her beloved great-uncle's health ailments. In this book, Sandry must contend with a new student, a blood feud, and a few new kinds of magic.
Trisana Chandler and her teacher, Niklaren Goldeye, have traveled south to the city-state of Tharios. Her teacher warned her about some barbaric customs, even though the Tharians are immensely high-handed and arrogant about their superiority. She discovers a new mage, who needs instruction, and becomes the guardian of the glass dragon Chime. Other matters are even more pressing, however, as a serial killer called The Ghost targets yaskedasi.
Pasco Acalon is a newly discovered dance mage with a very strict harrying family. Will they let him leave their harrying tradition to do what he really wants to do?
Vedris fer Toren has been the ruler of Emelan for decades, but his health makes it so he cannot do as much as he did before. As duke, he must stand against serial killers that seem to be invisible, and find a solution to save the people who look to him for protection. However, when the very person who seems to be able to stop the killers is his own beloved great-niece, will he be able to let her do what she has to?
Lark has looked after and taught Sandry for four years, but her student leaves Discipline to look after her great-uncle, whose health is failing. Lark must also figure out a way to stop the killers, as their magic has a deadly element.