I went to the cinema this evening for the first time in a while. I had sworn I wouldn’t go back after a dreadful attempt to watch one of the Jurassic World films. People talked throughout, scrolled on their phones, used torches to find snacks, and half an hour in a large family arrived and unpacked what felt like an entire corner shop. They never settled. We left.

Tonight was better, but not by much.

People drifted in after the film had started. It is a small thing, but it matters. The ads are there for a reason. Sit down, sort yourself out, and be ready when the film begins.

An hour into Lee Cronin’s The Mummy, a couple came in late, using their torches to find their seats, lighting up their snacks, talking, messaging. They stayed for half an hour, then left. Which raises the obvious question. What is the point of arriving that late?

And where were the staff? Why does Odeon Cinemas allow it? For an industry that relies on people leaving their homes and paying inflated prices for the experience, the least it can do is protect that experience once they are inside.

Maybe this is a London problem. I will find out tomorrow at Leicester Square, watching The Devil Wears Prada 2. Consider it a test. The Jurassic World fiasco happened at Odeon Luxe Lea Valley, where the reclining seats and Freestyle machines are about the only things in its favour.

In the meantime, I have reluctantly renewed my Odeon Limitless membership. On paper, it makes sense. In practice, it feels like a gamble. Perhaps the last screenings will be quieter.

Because the rules are not difficult. Sit down. Stay quiet. Keep your phone away.

Cinema etiquette is not complicated. The problem is that no one feels obliged to follow it anymore.