​Rules of theatre etiquette number one – arrive on time: Susan Morrison

Yes, you probably shouldn't have had that coffee. Or the giant bucket of Coca Cola, even if it was part of the meal deal.

You need to go, and go now, but you are not alone. An entire audience surrounds you and you are in the middle of the row and it's the best bit of the film.

You are about to block the view of the screen just as the villain is unmasked, the building explodes or the monster comes back to life.

Or worse, it’s live and a huge star of the British theatre is making his way to the front of the stage to crack out one of Bill Shakespeare’s big hit soliloquies.

The audience is geared up to listen and then there’s you, bumping along the row with a whispered solo speech of your own. Mainly comprising the words “Sorry”, “oops” and “ Can I just squeeze past?”

People are usually quite forgiving, though. Let's face it, in a few minutes, it might be them.

What is unforgivable, and weirdly I have seen this happening at just about every event I’ve been at since the Big Covid Shutdown, are the people who bump and grind their way along the row because they are late.

It happened at the big MacBeth production at Ingliston last month, where a couple barged in, bumbled about the auditorium trying to find their seats, then loudly did the ‘ooops, sorry’ manoeuvre along the row, which they did very carefully.

Well, they didn’t want to spill their drinks.

Yes, they had not only turned up late, but took the time to buy a pint of lager each before going in. The first act lasted over an hour. I think you know what happened next.

Seriously people, look at the show time. It's a play, not a dinner party.

If it says 7.30, it pretty much means exactly that, not 7.30 for 8.00. And for goodness sake, wait till the interval for that drink.