Marian Álvarez collaborates in this episode as Constanza. The actress would join the series as a regular cast member in season 14 playing Lola.
José Luis López Vázquez and Agustín González, two prestigious Spanish actors, make a cameo playing brothers.
Diana Palazón shares scenes with Octavi Pujades who plays a patient who is attended by Laura. Both actors become popular in Al salir de clase (1997) and worked together a few months in it.
Raúl Jiménez, who makes a brief intervention as Gollum, would collaborate in another four episodes the following year, in season ten, playing a different role, an student called Adrián.