Background

The films featured a regular cast of comedy actors. The mainstays of the series were Kenneth Williams (26 films including presentation of the compilation That's Carry On), Joan Sims (24), Charles Hawtrey (23), Sid James (19), Kenneth Connor (17), Peter Butterworth (16), Hattie Jacques (14), Bernard Bresslaw (14), Jim Dale (11), Barbara Windsor (10 including That's Carry On) and Terry Scott (7). Comedian Frankie Howerd is also associated with the Carry Ons, but only appeared in two films (Doctor and Up The Jungle) and the 1969 Christmas TV special.

The films' humour was in the British comic tradition of the music hall and seaside postcards. Many of them parodied more serious films — in the case of Carry On Cleo (1964), the Burton and Taylor film Cleopatra (1963).

The stock-in-trade of Carry On humour was innuendo and the sending-up of British institutions and customs, such as the National Health Service (Nurse, Doctor, Again Doctor, Matron), the monarchy (Henry), the Empire (Up the Khyber), the military (Sergeant) and the trade unions (At Your Convenience) as well as the Hammer horror film (Screaming), camping (Camping), foreigners (Abroad), beauty contests (Girls), and caravan holidays (Behind) among others. Although the films were very often panned by critics, they proved very popular with audiences.

The series began with Carry On Sergeant (1958), about a group of recruits on National Service, and was sufficiently successful that others followed. A film had appeared the previous year under the title Carry On Admiral; although this was a comedy in a similar vein (with Joan Sims in the cast) it has no connection to the series. There was also an unrelated 1937 film Carry On London, starring future Carry On performer Eric Barker.

The cast were poorly paid — around £5,000 per film for a principal performer. In his diaries, Kenneth Williams lamented this and criticised several of the movies despite his declared fondness for the series as a whole. Peter Rogers, the series' producer, acknowledged: "Kenneth was worth taking care of, because while he cost very little [...] he made a very great deal of money for the franchise."