While exploring the National Library, Miaka Yuuki and Yui Hongo come across an odd antique book that emits a red glow, pulling them into a foreign realm. Upon arriving, they face hostile slave dealers and manage to flee with aid from Tamahome, a strong young man marked with a Chinese character on his forehead. However, the red light soon reappears, whisking Yui away.
Determined to find her friend, Miaka seeks Tamahome's help. The situation intensifies when they meet Emperor Hotohori, who thinks Miaka is the prophesied priestess of the kingdom's guardian deity, Suzaku. By assembling the god's seven Celestial Warriors, the priestess can call upon Suzaku to grant any wish. Hotohori hopes this will rescue his nation, and since it also seems like a good way to solve Miaka's problems, he persuades her to take on the role.
Back at the library, Yui realizes she has returned alone. Unable to act, she watches helplessly as Miaka undertakes brave challenges as the heroine of the mysterious book.