Seonglae ChoThe watershed is at 9 p.m., so as a rule, content that may be unsuitable for children should not be broadcast before then. After 9 p.m., the permitted range becomes much broader, including swearing, sexual content, and strong depictions of violence. Under Ofcom standards, this period generally runs from 21:00 to 05:30.
In the UK, when people say “It’s after the watershed,” they do not simply mean “it’s past 9 p.m.” It can also be used jokingly to mean “now it’s okay to talk about something a bit more explicit or adult.”