Agatha Christie's original Tommy and Tuppence novels were written and set in different periods ("The Secret Adversary" and "Partners in Crime" in 1920s; "N or M?" in 1940s during World War II; "By the Pricking of My Thumbs" in 1960s; "Postern of Fate" in 1970s). But in this TV series, all stories are set in 1950s.
The first three episodes are based on the first book in the Tommy and Tuppence book series "The Secret Adversary". The three last episodes are based on the third book in the series "N or M?". Despite the tv series' title being "Partners in Crime" (the same title as the second book, comprised of 17 short stories) it contains none of the stories from the book.
Parts of the series were filmed at Cromer in Norfolk, England, including the pier and The Wellington public house on New Street.
The Beresfords' house was filmed on location in Oak Hill Crescent, Surbiton.
The show was canceled by BBC after only one series.