The men shake hands, make polite noises, assess one another. Mr Somers is a Member of Parliament. They establish other common acquaintances and share common views on the state of the nation, raising their voices as the music swells.

Ruby waits, listens, says nothing, because she is not expected to speak – and she has little to contribute.

‘But we’re not here for serious conversation, Lazenby,’ Haversham says, after a time. ‘I brought Somers here for light relief. Fun, dancing and all that.’

‘Then you should spend the evening with Ruby.’ Peter puts an arm around her waist and draws her closer to the group. ‘I’m sure she can offer you a pleasant time – without needing to talk politics. Ruby?’ He tilts his head. ‘Would you like to take Mr Somers for a dance? He looks as though he’ll be less clumsy than me.’

The handsome man laughs at this and nods to Ruby. ‘Well, I’d be delighted, although I can’t vouch for my dancing.’

‘I need to go and greet a few people – always the duty of a good host – and Miss Mills needs to dance.’ He hands her to Alex Somers with a gentle squeeze of her fingers.

So, this is it. This is her occupation for the evening. This one. She smiles up at her dance partner. She takes a breath.

‘I do need to dance. He’s quite right.’ She uses one of her better voices for this man. Not too plummy – he’ll be used to proper ladies, and he’ll soon recognise her for what she is if she tries too hard. She sounds as light as air, breathy, vague, girlish. Just the sort of girl to take his mind off weighty matters of state. He is a better prospect than a dock worker or smelter. She squashes down all thoughts of Daisy, standing in her grubby nightdress in the candlelit gloom of the Borough, and of the rough-looking girl in the ladies’ room. She shivers. The tiny beads sewn on her dress catch the light, making her body sparkle.

Peter meets her eye as he takes his leave with Charles Haversham. He wants her for himself; she can see it. She turns away, briefly revelling in this, and leads Mr Somers to the dancefloor.

He is a competent dancer, but a little lazy. She far preferred dancing with Peter. This one, she suspects, has not danced in a while and she needs to pay attention in order not to be stepped on. He is the sort who would prefer to sit and talk, perhaps. After a couple of dances, she pretends thirst, and he readily escorts her to a table in one of the quieter alcoves and calls for champagne.

‘It’s good to dance,’ he says. ‘I hope I didn’t tread on you too much. I’m woefully out of practice.’

‘I would never have guessed,’ she says. ‘You move very well.’