The series follows British diplomat Laura Simmonds, who, with her Barcelona Consul colleague and friend Alba, is determined to fight in order to protect British nationals involved in a series of conflicts in Barcelona.[5]
On 8 July 2020, The Diplomat was commissioned by British pay television channel Alibi in partnership with BBC Studios as the third UKTV Original for Alibi.[6] Executive producer and UKTV drama commissioner, Philippa Collie Cousins stated that both main characters (Laura Simmonds and Alba Ortiz) "are contrasting professional working women dealing with murder, abductions, and organised crime, alongside managing their careers and love lives." Regarding the writing and storyline, Cousins stated that "it is The Good Wife meets Spooks for 2021, a feisty workplace drama set in Barcelona with cracking dialogue, abundant crime and a surprising series arc. Television to stay in for by the very talented Ben Richards. I am very excited to work with such an expert lead writer as Ben, but equally excited to add talented up and coming writers to the writing team."[7]
Casting
On 25 April 2022, Sophie Rundle was cast as lead character Laura Simmonds.[8]
Filming
Filming began in April 2022 in Barcelona, Spain.
Title conflict
An unrelated American series with an identical title, set in London and centred on a new United States ambassador to the UK, was announced in 2022, two years after the British series was announced, and released worldwide on Netflix on
20 April 2023, only a few weeks after the UK programme concluded its first series. The British newspaper i quoted an unnamed source close to the UK series as being frustrated by the title choice for the Netflix series, fearing it would confuse viewers and complicate international rights sales for the Alibi series, which are handled by BBC Studios. Neither party has indicated a willingness to change the title to avoid confusion.[9]