It feels like this initial "Carry On" movie couldn’t escape being weighed down by comparisons to the much more amusing and impactful wartime comedies starring Will Hay and Norman Wisdom. Those earlier films had a sharper, immediate sense of dark humor because they were created while bombs were actually falling during the war. This one comes across as simply a collection of jokes and suggestive content that doesn't manage to elevate itself above a pretty thin narrative, some rather childish lines, and performances from a cast who seemed somewhat unsure and unable to really stretch out the fragile storyline. The plot revolves around "Sgt. Grimshawe" (William Hartnell) wanting to finish his career with a flourish by leading his group of inexperienced men and women to victory in the "Star Squad" competition. What follows is a watered-down version of slapstick comedy, with jokes that are obvious and some rather uninspired portrayals of familiar character types – the kindhearted but not very bright, the intelligent but unlucky, and those struggling with sexual frustration—and none of it really resonated with me. Although it's just under eighty minutes long, it dragged on, and I found myself getting bored around the middle. Things should hopefully improve from here.

Source on TMDB