Japan, 1562. Young Nariko finds herself on a farm for misfit girls after she narrowly survives a brutal samurai attack on her family. But the farm hides a secret: it is a training camp for a secret army of all-female ninja. Smart and brave, Nariko is a valuable spy, and she soon finds herself drawn back into the very war that tore her family apart, as she is haunted by unanswered questions about her past.