When Angela (Ana Torrent) is accessing the warranty database, director Alejandro Amenábar's name appears as a warranted customer of an XT-500 video camera.
The film had a relatively small budget of P116 million - equal to about 696,000 EUROS.
Alejandro Amenábar wrote some of this film while still at University, and that University was the Complutense, as featured in this film.
The story Chema tells Angela is "The Birthday of the Infanta" by Oscar Wilde. Although written by a British author, it takes place in Spain.