The Major Tones (Los tonos mayores)

Fourteen-year-old Ana lives in Buenos Aires with her dad, Javier. Following an accident, she has a metal plate inserted into her arm, which she starts to feel mysterious pulses through. Without mentioning anything about it to Javier, she works with her friend Lepa to compose a melody, “The Heartbeat Song,” inspired by the rhythmic signals.

It actually turns out they are words in Morse code. After realizing that her arm is an antenna to an unknown mystery, Ana becomes determined to decode the words. As she delves into the labyrinth of secret messages, she distances herself from her friend and her dad. Her previously harmonious life is transformed by obsession as she wonders if the coded words are addressed specifically to her.