Illyasviel von Einzbern is an ordinary elementary school student who becomes a magical girl when the magical Kaleidostick Ruby deems her a more suitable master than the sorceress, Rin Tohsaka. Rin, who had been tasked by the wizard Zelretch to collect the seven Class Cards containing the spirits of Heroic Spirits from legend, finds that she is unable to change Ruby’s mind and must supervise Illya in completing the task of collecting the Class Cards. During Illya’s adventures, she receives a friend and rival in a girl named Miyu, the contracted master of the Kaleidostick Sapphire, which similarly abandoned its original master and Rin’s rival, Luvia Edelfelt.The magical girls are back, and ready for another round of adventure! After successfully recovering the Class Cards, fifth graders-turned magical girls Illya and Miyu think they can finally take it easy. But as fate would have it, the girls are once again called back into active duty when they find out that the Cards have left some very nasty side effects on their world. However, their seemingly easy mission goes totally awry with the appearance of a dark stranger who looks just like Illya! Who is this new but familiar face, where did she come from, and what does she want from Illya? With the arrival of this new foe, it seems like Illya’s finally met her match when her everyday life takes one dark turn!