Gael García Bernal fired off an angry riposte to New York Times reporter Lynn Hirschberg after she claimed that he had fallen out with Pedro Almodóvar over filming the explicit homosexual love scenes in the film. Bernal wanted it on record that he had had absolutely no reservations about taking the role.
The film opened the 57th Cannes Film Festival in 2004. It was the first Spanish film to ever get that honor.
Mexican-born actor Gael García Bernal had to be able to do a convincing Spanish accent before Pedro Almodóvar would allow him to get his role(s) in the movie. Bernal also had to master Spanish body language. He took flamenco lessons to help him do that. He also studied the films of Barbara Stanwyck and Spanish camp icon Sara Montiel, as well as Almodovar's previous leading ladies, Carmen Maura and Victoria Abril. When asked, however, if there was a particular femme fatale he sought to emulate, Bernal's response was Alain Delon's sexually ambiguous Ripley in Purple Noon (1960).
Pedro Almodóvar dedicated the opening night performance at the Cannes Film Festival to those who had been killed in the al'Qaeda terrorist train bombings in Madrid the previous month.
At the beginning of the movie, there's a poster of a fictitious film called "La abuela fantasma" on the wall in Enrique's studio (it's clearly visible when Ángel leaves after giving his screenplay to Enrique). "La abuela fantasma" was the original title of another Pedro Almodóvar film, Volver (2006).