A top secret chemical formula has been stolen by STENCH (the Society for the Total Extinction of Non-Conforming Humans). Fearful of the formula falling into the wrong hands, the chief of the Secret Service reluctantly sends the only agent he has left, the bumbling and silly Agent Desmond Simpkins, (Kenneth Williams), and his three trainees, Agent Harold Crump, (Bernard Cribbins), Agent Daphne Honeybutt, (Barbara Windsor), and Agent Charlie Bind (Charles Hawtrey), to retrieve the formula.
The agents travel separately to Vienna, where each makes contact with Carstairs (Jim Dale), who assumes a different disguise each time. Next, they rendezvous at the Cafe Mozart and later travel on to Algiers. Upon the way, they encounter the STENCH agents, the Fat Man and Milchmann (who stole the formula disguised - befitting the English translation of his German name - as a milkman). Unfortunately, the agents' ineptitude results in Carstairs being floored in an encounter with the Fat Man.
Daphne and Harold attempt to steal the formula back whilst disguised as dancing girls in Hakim's Fun House, where the Fat Man is relaxing. The agents also encounter the mysterious Lila (Dilys Laye), whom they are uncertain if they can trust. With the STENCH henchmen close on their heels, the agents have no other choice but to have Daphne memorize the formula with her photographic memory, before the four of them destroy the formula papers by eating them with soup.
The four agents end up captives of STENCH. Daphne is interrogated by the evil Dr Crow (played by Judith Furse and voiced by John Bluthal), head of STENCH, but she fails to succumb until she accidentally bumps her head, causing her to reveal the formula. Simpkins, Crump and Bind escape their cell and collect Daphne and Dr Crow's tape recording of Daphne's recitation, but are caught up in an underground automated factory process, from which they escape only when Lila pulls a gun on Dr Crow, forcing her to reverse the process.
Simpkins sets the STENCH base to self-destruct before rushing into a lift with the other agents, as well as Lila and Dr Crow. As the lift ascends, Lila reveals to Simpkins that she is a double agent, working for SNOG - the Society for Neutralising Of Germs - and she has a crush on him. The lift reaches the surface, which is revealed to be the office of the chief of the Secret Service; the headquarters of STENCH are right below the streets of London. STENCH headquarters self-destructs, choking the chief's office in a thick cloud of smoke.Screenplay – Talbot Rothwell & Sid Colin
Music – Eric Rogers
Songs – "Too Late" by Alex Alstone & Geoffrey Parsons and "The Magic of Love" by Eric Rogers
Associate Producer – Frank Bevis
Art Director – Alex Vetchinsky
Director of Photography – Alan Hume
Editor – Archie Ludski
Camera Operator – Godfrey Godar
Assistant Director – Peter Bolton
Unit Manager – Donald Toms
Continuity – Penny Daniels
Hairdressing – Biddy Chrystal
Sound Editor – Christopher Lancaster
Sound Recordists – CC Stevens & Bill Daniels
Costume Designer – Yvonne Caffin
Make-up – WT Partleton
Producer – Peter Rogers
Director – Gerald Thomas
Albert R. Broccoli, the producer of the James Bond film series, objected to the character name "James Bind agent 006½" (intended for Charles Hawtrey) and threatened legal action. Producer Peter Rogers therefore changed the name to Charlie and the agent's code number to double 0 – ooh! Poster artist Tom Chantrell also had to modify the poster when similar complaints were voiced that the artwork was too similar to From Russia with Love.
The film pokes fun at various spy movies, James Bond being the least of them. They include The Third Man (coincidentally, Eric Pohlmann – who played The Fat Man – also had a minor part in The Third Man), and Casablanca. One or two of Crow's female assistants wear hairstyles similar to that of Modesty Blaise, whose adventures had started in the London Evening Standard the previous year.Filming dates – 8 February-13 March 1964
Interiors:Pinewood Studios, Buckinghamshire
Carry On Spying received critical acclaim, with critics praising its fast pace, satirical intent and Kenneth Williams's performance which was largely based on his "Snide" persona from Hancock's Half Hour. It currently holds a 100% 'fresh' critical rating on Rotten Tomatoes, based on 5 reviews and a 62% audience score based on 912. It is generally considered one of the finest films in the series, alongside Carry On Camping, Carry On... Up the Khyber and Carry On Matron.