Now, she reaches the corner of Duke Street and the impressive façade of Selfridges. The flags on the roof hang limp in the grey morning, but the recently cleaned colonnade is shining, and the new extension has made the building even more imposing on this section of Oxford Street. Privately, Harriet thinks Selfridges a little vulgar, but never says so in public because this is her mother’s view. Instead, she vigorously defends Mr Selfridge’s stance on women’s suffrage and lauds his store’s imaginative window displays and spacious interior – received opinions she has heard voiced by people more forward-thinking than her parents.

She breathes deeply as she enters through the vast doorway and is greeted by the beautiful fragrances. She closes her eyes and revels in the appealing amalgamation of scents.

She must concentrate. She decides to begin at the top of the store and work her way down. She will ignore the restaurant, the bookshop and the gentlemen’s clothing. She cannot imagine that Ruby will be booking theatre tickets or sending parcels at the store’s postal service, either. At least here, unlike other places, she may ascend and descend the floors at speed by using the lifts.

It is almost an hour later, when she is on nodding terms with one of the female lift attendants because she has ridden in the lift so much, that she catches sight of Ruby.

She is at a counter near the rear of the ground floor. It does not surprise Harriet to see that she is examining jewellery. It is not fine quality, such as one might find at Mr Carrington’s, but mere imitation. Glass beads threaded on string, paste diamonds fashioned into brooches or hatpins.

Ruby is wearing her pale blue Poiret and a light brown hat. It sits close to her head and is pulled low on her brow, but Harriet would recognise her anywhere; she moves with such grace and poise. Harriet watches, transfixed, as Ruby lifts strands of purple beads from the metal stand and dangles them above her head, to see how long they are. She tilts her head to one side, as if considering whether to make a purchase – or possibly whether to steal them. She might have a care in this store. Selfridges has recently, and very publicly, employed more floorwalkers in an effort to deter thieves. Harriet readies herself to fly to her aid, to buy the beads herself if Ruby slips them into her pocket.

Thankfully, she sees Ruby speaking with the assistant at the counter. It appears that the girl is buying rather than stealing today.