Across a kaleidoscope of dazzlingly coloured evening gowns, jewelled tiaras and a forest of blue and scarlet uniforms, she sent back her own joyous message: I know. I understand.

The opening dance was a stately polonaise. To her surprise, her father danced it very well, but it was also a dance that, being processional, made it easy for other dancers to get a clear, close-up view of her. Determined not to let Ella down, Alicky kept a fixed, frozen smile on her face, knowing that every minute she endured was a minute closer to being with Nicky again.

After the polonaise it was a waltz, and Sergei, handsome and unbelievably tall and erect, waltzed her with military precision around the crowded ballroom floor. Occasionally she caught sight of Nicky waltzing with a beautiful dark-haired girl. Diamonds were threaded through the girl’s hair, and she and Nicky were talking animatedly to each other. Nicky wasn’t looking at the girl in the way he looked at her, though. One more dance. That was all that had to be lived through. Just one more dance.

‘Trust me to have drawn a mazurka,’ Ernie said in mock despair, when Sergei had returned her to Ella. ‘Am I allowed to improvise?’

‘If you draw a shred more attention to me than I am already receiving,’ she said through gritted teeth, ‘I swear I will never speak to you again as long as I live.’

Ernie laughed and then, as she had known he would, danced the intricate heel-clicking, foot-stamping steps perfectly. Because of its exhilaratingly fast tempo, the mazurka was one of Alicky’s favourite dances, but, for the first time ever, she couldn’t wait for it to end.

As she stood once again at Ella’s side, her heart beating fast and light, she saw Nicky begin walking towards her; saw people making way for him; saw how closely they were watching to see who it was he was about to dance with.

He came to a halt in front of her and bowed. ‘My dance, I believe, Cousin Alix.’

The dance was another waltz and as the orchestra began playing Strauss’s ‘By the Beautiful Blue Danube’, she slid rapturously into his arms.

He said with a shy smile in his voice, ‘You don’t mind me calling you “Cousin Alix”, do you?’

‘No.’ Incredibly she, who suffered from such crippling shyness that she could barely function socially, was not at all shy. In Nicky’s arms she had never felt safer, more secure or more confident, and that he – the Tsesarevich and an army officer – was shy won her heart in a way no amount of self-important arrogance could ever have done. ‘I have forgotten,’ she said, ‘in what way we are cousins, for I know that we are not first cousins.’