Escorts in Bond Street, W1S, as the Society arranges them after dark

The southern half is Old Bond Street, laid out first and short enough to walk in two minutes. North of the Burlington Gardens crossing it becomes New Bond Street and runs on to Oxford Street, four times the length and twice as busy. Only the postmen and the auctioneers distinguish between them; everyone else says Bond Street and points.

The trade is jewellery, watches, couture and art, which means the street keeps banking hours and empties at six with the abruptness of a theatre after a matinee. The saleroom on the New Bond Street side lights its first floor late into the evening when a sale is coming, and the Victorian arcade near the southern end stays lit after the shops behind it have shut. Halfway along, Roosevelt and Churchill share a bronze bench with a gap between them, which by half past eight is the only seat on the street anybody is using.

Guests who write from here are dealers, collectors, and people in London for three days of appointments that all fall inside four hundred yards of pavement. They are not looking for a night out so much as for the evening that should follow a good day, and for company who can hear about the day without needing the whole of it explained.

Five houses sit within a few minutes of the pavement. Nothing connects the Society to any of them. They are printed for orientation, and a companion who walks into one is simply somebody's guest for the evening.

W1S 2YF stands at the Conduit Street corner and is the closest thing the street has to a local, with a small panelled bar that fills at six with people who have been on their feet since ten. W1S 4BP is four minutes west on Albemarle Street. W1B 4DY lies five minutes south east where the street reaches Regent Street.

Two more are a short walk north: W1K 6TF, behind Grosvenor Square, and W1K 4HR, five minutes along Brook Street from the New Bond Street crossing. Serviced flats above the shops account for the rest of what Cressida arranges in this postcode.

Bond Street station sits at the top of the street, about two minutes from the northern end, and carries the Jubilee, the Central and the Elizabeth line, the last of which reaches Heathrow without a change. Five minutes north east, Oxford Circus adds the Bakerloo and the Victoria. Green Park lies seven minutes to the south.

Your companion travels by car regardless, and for anything inside the first two zones the Society pays the driver. The useful hour in W1S is the one between six and seven, when the shutters come down and the street becomes pleasant: write to Cressida during the afternoon and a companion can be with you as the last grille rattles shut.

All she needs is the reservation name and the room number, or a street door if you are in a flat above the shops, and she repeats it to you in writing. Your companion collects the fee from you as she reaches the room, and no sum is added on top of it.

A guest with three days of viewings writes at four: company from half past six, two hours, £1,100. Cressida sends Luna, who has spent the afternoon somewhere with better light than his.

They meet in the bar at the Conduit Street corner and leave it after one drink. The walk south takes eight minutes and includes a long stop at a window neither of them can afford and a shorter one at the bench, where she reads the inscription aloud in a voice that makes it funnier than it is. Dinner is on Bruton Place, four minutes further on. He is back at the hotel by half past nine with his appointments intact for the morning.

Luna, Samanta and Angelika live in Mayfair and reach the street on foot. Rosa comes down from Marylebone, just across Oxford Street, and knows the gallery rooms on the side streets better than most dealers do. Liana travels the same short distance.

Vanessa comes in from Paddington and has views on every scent counter between here and Piccadilly. Bianka and Sonya cross from Knightsbridge by Hyde Park Corner. Anyone on the roster will come to W1S.

South, past the arcade, the street runs into Piccadilly and the hotels along it. A few steps east of the southern end lies Berkeley Square, where most of these walks are heading. North west, Brook Street carries you to Grosvenor Square in five minutes, and the whole district is described on the Mayfair page. For where the evening might end afterwards, there is a note on late dessert and digestifs.