The only people who knew what the card said were actor Luis Arrieta and director Luis Javier M. Henaine.
Production Designer Christopher Lagunes and Cinematographer Diego García, also worked on the short film El Sonido Del Silencio.
On the first scene of the movie, Cassandra Ciangherotti really hit herself on the table, up to the point where she got a big bump in her forehead. It is still visible in the following scene.
Humberto Busto was the first and only choice for the character of Niko, because of this, he was also the first actor to be cast in the movie, four years before the film even started production.
Unofficially based on the short film "El Sonido Del Silencio", which the director wrote and directed ten years before, while still in college.
Paloma Woolrich and René Gatica are the only actors to reprise their roles from the short film.
To show that time had passed, the last scene was filmed a month after principal photography ended.
Luis Arrieta and Cassandra Ciangherotti had previously worked together in Paradas Continuas.