It's not difficult to recognize stories that have been reverse-engineered, those that fashion individual characters and contrive to bring those disparate souls together in the most convenient way possible. Far more rare is the tale that begins from a center and organically evolves, unwittingly capturing its ancillary players. Carlos Vermut's "Magical Girl" certainly feels like the latter, weaving its troubled lives together with ample sorrow. The impetus for all of this intrigue is a sudden hospital visit for Alicia, a 12-year-old girl living with leukemia. Her father Luis (Luis Bermejo) learns that Alicia is terminal (a detail never explicitly stated but delivered in the first clear example that Vermut is in complete control of his story). After Alicia is released, he stumbles across Alicia's diary, discovering her wish to own a dress identical to one worn by her favorite anime star. When the price tag turns out to be far beyond his dwindling savings,...