ITV commissioned the miniseries in December 2020, with filming beginning in March 2021 in Liverpool, Wirral and Shrewsbury, plus additional locations in Croatia including Zagreb, Split, Rijeka and Opatija.

Unlike previous adaptations, the TV series heavily reworks Len Deighton's original novel, altering the plot and several characters and adding a lot of new material, making it significantly different from the source material.

The series borrows the character names 'Harry Palmer' and 'Jean Courtney' from the 1965 film adaptation, names that were actually coined for that movie rather than taken from Deighton's novel, which never names its narrator.

Director James Watkins pays visual homage to 1965 film director Sidney J. Furie by using similar angled camera work, and in some scenes recreates the framing almost shot-for-shot.

The opening sequence of episode one, featuring coffee grinding and coffee making followed by a shot of Palmer's glasses coming into focus, is a deliberate 'little wink' homage to the iconic opening of the 1965 film, as confirmed by director James Watkins.

Visual effects for the series were created by the UK-based company Koala FX.

Critics were divided over the casting of Joe Cole as Harry Palmer, with some calling him 'horribly miscast' and 'too young looking, too choirboy-pretty', while others praised his 'cocky insouciance' and felt he grew into the role over the course of the series.