It’s a question that family and friends often wonder about, when a loved one appears to have got a little… confused. At what point can you have them bundled into a private ambulance? Is there a specific sign? A recognised action? Well, yes.

It’s when the beloved friend/father/brother/cousin arrives over an hour late for lunch, claiming that they thought today was tomorrow, and on taking their seat, looks at a neighbouring table and steals a chip. And then another.

The soon-to-be inpatient believes this to be reasonable behaviour, but not the diners whose chips are now down, and who, repulsed by this, abort their lunch, call for the bill and leave.

Yes, I think that is the moment you can reasonably press the help-needed klaxon and wait for your acquaintance to be removed. But not before you’ve both had a good lunch, of course. 

And as I don’t like dining alone, and had already sat in Fallow for over an hour, I wanted company while I ate, even if the chap opposite me needed a psych assessment.

Fallow is a new place for a place that started in a different place before lockdown. It’s the creation of two chefs who met at the stove of Heston Blumenthal’s Dinner – presumably while pondering a way out of prepping a thousand meat fruits (a dish of chicken liver parfait disguised as a mandarin) each week.

They won praise for residencies as they tested the water around London, then opened on Heddon Street, off Regent Street, for 10 days before a plague shut them down.

Now they are reborn on St James’s Market, in a modern building with large glass frontages, a big bar, an open kitchen, and with mushrooms growing above the pass and seaweed hanging from the ceiling.

The kitchen is lit seemingly from below, like a Joseph Wright of Derby painting, the industry of the chefs focusing not on bird experiments, but on extracting flavour from simple British ingredients. And this they do with considerable panache. Take their mushroom parfait, for example.