One never knows where the forces of evil may be preparing to strike, but fortunately for the citizens of the city of Sorasaki, there is a secret group of mysterious protectors who stand ever ready to fend off the pernicious plans of sinister scoundrels, malevolent malefactors and nefarious ne'er-do-wells. But who are these heroes and how are they recruited? Momo Minamoto is a normal high school student who dreams of one day becoming a police officer like her late father, but when she investigates the case of a missing friend, she quickly finds herself being recruited into the ranks of the Tsukikage, a group of high school girl spies with above average abilities and the ferocious fighting skills needed to take on any fiend who foments foulness and corruption! Stand back evildoers!