The plot follows the plight of Basque politician Manu Aranguren, the contact person in the negotiations between ETA and the Spanish government.

The film was produced by Sayaka Producciones, and it had the participation of ETB, the Basque Government, and Canal+.

[7] Negotiator was presented in the 'Zabaltegi' section of the 62nd San Sebastián Film Festival in September 2014.

[8][9] Neil Young of The Hollywood Reporter considered Negotiator a "briskly amusing" film, otherwise writing that "droll peek behind political headlines is elevated by strong, engaging performances".

[9] Javier Ocaña of El País billed the film as "a historic film for our cinema and for our society" [...] pursuing "a painful, black, brilliant, tragic and atrocious humor, about the deformation of language, about the miseries of the recent history of the Basque Country, about the miseries of the human race".