I tend to be slightly iffy on films which have been adapted from plays for cinema - often I feel that it is pointless to recreate a stage play set in a confined location, as it adds very little to the source material. Although I have not seen the play which this film was based on (written by its director), I feel that El Rei Borni is a fairly justified adaptation, as the film's editing enhancing the comedic timing of the jokes.
The performances are very good from all of the cast, particularly the lead character of David, played by Alain Hernandez, who manages to gain the audience's empathy despite being an unlikable character. There are also plenty of great, twisted jokes and I laughed a lot throughout the film.
The film is excellently directed by Marc Crehuet, with a great sense of energy and pace, and also has very good, unconventional cinematography for a comedy film (albeit a very dark one).
The film is very short, with a run time of only 87 minutes, and could possibly do with being a little longer as the ending feels a little too soon. However, as the dialogue is very fast paced, this is not a big issue.
Overall, I would recommend El Rei Borni as an excellent dark comedy and political think-piece, which can be enjoyed by foreign film-fans and general audiences alike.