Director Álex de la Iglesia considered casting Fernando Esteso as Nino and Andrés Pajares as Bruno.

The principal theme of the soundtrack is based on Los pekenikes's song Embustero y bailarín (Liar and dancer).

Bruno and Nino drive the exact same model of Mercedes, and their license plates are consecutive.

Director Alex de la Iglesia made a cameo as a staff member on a tv show

Sixto Cid (aka Sixto 'Piti' Cid), who plays Fakir, appears in credits by a mistake as Cid, and his character as Fakir Sixto 'Piti'.