Does the cinema ticket inspector just check in?

No. The ticket inspector's job is mainly to check tickets, and check tickets 20 minutes before the screening 15. In addition to ticket checking, it also includes guiding the audience to the admission route, maintaining the order of entry and exit, handling special situations such as fake tickets and evasion, and being responsible for the distribution and recycling of 3D glasses (depending on the configuration of 3D glasses in the cinema).