This later Carry On is missing Sid James, Hattie Jacques, Barbara Windsor and Charles Hawtrey. Popular regulars Kenneth Williams, Joan Sims, Bernard Bresslaw, Kenneth Connor, Patsy Rowlands, Jack Douglas and Peter Butterworth are in substantial roles and are great. However the departed regulars are missed.
The story works well. It is essentially a series of sketches about various people at a campground, but the story threads form a cohesive whole.
Some characters work better than others. Ian Lavender and Adrienne Posta as a young couple with a huge dog don't seem to have been given any jokes. Their scenes are pretty limp and peter out with no punchline. This brings down the pace of the film.
The characters played by Bresslaw, Rowlands and Sims develop nicely as the film progresses. Sims starts as a battle axe but becomes more sympathetic.
The scenes with Jack Douglas and newcomer Windsor Davies as mates on a fishing holiday (with Davies hoping to hook some dolly birds) work well, and are funny. Davies does the impossible - successfully stepping into the Sid James role. Newcomers Carol Hawkins and Sherrie Hewson acquit themselves well as the young women unfortunate enough to have them in pursuit.
Kenneth Williams and guest Elke Sommer are archaeologists studying the old cesspool. Their bits are classic Carry On and very funny. Sommer fits in seamlessly and is the series' most successful guest star.
Kenneth Connor as the lusty owner of the camp site and Peter Butterworth as the scruffy odd jobs man are great too.
Liz Fraser returns after many years' absence but only has a small role.
Look out for Larry Dann as the main university student in the film. Dann had appeared in Carry On Teacher (1959) as a student, and this film saw his return. He went on to roles in England (1976) and Emmannuelle (1978), then was a long running regular in police TV series The Bill.