Serrano is a Spanish screenwriter and director. Just before graduating with a degree in computer science he gave up his studies and devoted himself to film. In the beginning he directed short films (El primerizo, 1993; Mezclar es malísimo, 2001) for which he wrote screenplays. He wrote his first screenplay for a feature film The Other Side of the Bed (El otro lado de la cama, 2002), which was directed by Emilio Martinez Lázaro and had the most viewers in Spain in 2002. Serrano wrote the sequel The 2 Sides of the Bed (Los 2 lados de la cama, 2005) as well, which, unlike the original, was not very successful. His directing debut was the comedy Soccer Days (Días de fútbol, 2003), and he later made Días de cine (2007). He also wrote screenplays for both of these films.