Tuchi longs to join in and play with the school's mariachi band, but it's the 1970s and in her community, mariachi is only for the boys. Still she hopes—and wishes on Seńora Luna. When Tuchi stumbles across her nana's guitarrón, Nana teaches her to play in secret. The music rumbles inside Tuchi like desert thunder. Will Tuchi be ready for the big audition? And will Seńora Luna help Tuchi make her wish come true?