The "Ninja Schoolgirl" videos have gone viral in Japan, earning 600 million views on YouTube in only a month. In them, a couple of young, uniformed girls pull moves that are half parkour stunts and half Chow Yun-Fat from Crouching Tiger. The girls flip off buildings, scale walls, and bust out flying kicks all while dressed like they're skipping Sophomore Econ class.VICE Japan tracked down the new internet stars to get a behind-the-scenes look at the making of their viral video.