After wreaking devastation on the general public, governments throughout the world shifted to a more elusive method to achieve their agendas—a battle conducted in the shadows. Lily, a lovely young lady with white hair, is a student at one of the many institutes that prepare young people to become excellent spies. Unfortunately, despite performing well in the academic tests, she only manages to pass her practicals with flying colors. With no real-world skills to speak of, her chances of graduation are bleak—that is, until she is invited to join the mystery squad "Tomoshibi" and participate in an Impassable Mission. Lily happily welcomes the opportunity to work with the top. When she gets to Kagerou Palace, however, she is rendered speechless. The actual purpose of Tomoshibi and its terrible predicament are revealed. Lily discovers that this is not the idyllic excursion she had envisioned when she is joined by other troublesome female spies and a mystery young man leading the operation.