Mahou Shoujo Madoka★Magica Movie 1: Hajimari no Monogatari

In the city of Mitakihara, a girl named Madoka Kaname, along with her friend, Sayaka Miki, encounter a creature named Kyubey and are saved from witches by a magical girl named Mami Tomoe. Kyubey offers Madoka and Sayaka the chance to have any one wish granted in exchange for becoming a magical girl and fighting witches, whilst Homura Akemi, another magical girl who recently transferred into Madoka's class, is strongly against Madoka becoming one. Before Madoka can make a decision, however, Mami is killed by a witch, leaving Madoka too afraid to become a magical girl. Sayaka, however, decides to become a magical girl herself in order to heal the hand of her childhood friend, Kyosuke Kamijou. As Sayaka soon comes into conflict with another magical girl named Kyouko Sakura, they, along with Madoka, learn the shocking truth that their soul gems, the source of their magical powers, literally contain their souls. (Source: ANN)