Tatsuko Yaezaka, a freshman in high school, is being pursued by ninjas who are all apparent representatives of "Iga" from different countries. It's unclear why she's being targeted, but it seems to be related to something called the "World Ninja Record." Fortunately, Tatsuko is well-versed in how to defeat ninjas, thanks to her childhood friend from Japan's Iga. However, she may struggle to outsmart America's Iga.