Rosa met the horse halfway across. There was a sense of expectation in the frosted air as it gazed at the plum in her hand. She held the sparkling fruit up to the clockwork creature, who sniffed at it for a moment before gently taking a large single bite. Purple juice stained the animal’s muzzle as it chewed and swallowed, one bite after another, until the entire plum was gone, stone and all.

The horse snorted its satisfaction in icy puffs of air and tossed its head, its golden ribbon shining in the winter sunlight. It looked unchanged and Rosa wondered whether she’d misplaced her hopes after all. The horse turned away and pranced back to the carousel, with Rosa following slowly behind. The only way to know for sure was to test it. She pushed the lever to operate the carousel and then climbed up onto the platform.

The horse with the golden ribbon whickered as she climbed up onto its back. She picked up the reins and concentrated hard on the moment to which she wished to return. The carousel picked up speed around her, its music filled the air and then the icicles, and the horses, and the ribbons faded away, and she was no longer on the ice at all, but back in the parlour of her family’s London town house.

Rosa sat on a high-backed sofa and Eustace had just bent down on one knee before her. ‘I hope,’ he said, ‘that you will do me the great honour of becoming my wife.’

The memory was all just as Rosa recalled it. Whenever she had visited this moment in the past, she had tried to give a different response, but had always been compelled to utter the same one over and over again. Her mother had impressed upon her the importance of being decorous and dignified when accepting a proposal, but the utter thrill of having won a duke had caused Rosa to forget all that. She had leapt to her feet and almost knocked Eustace down with her embrace.

‘Oh!’ she had cried. ‘I thought you would never ask!’

Try as she might, she had never been able to get the scene to play out differently in any way at all. Until now.

‘I am not sure,’ she said. ‘I would like some time to think about it.’

Eustace looked surprised, but not as shocked as Rosa was herself. She had done it! Spoken entirely different words and acted in an entirely different way.

‘Of course,’ Eustace said, rising to his feet. ‘It is a momentous decision.’

Rosa looked at him. ‘Might I say anything at all?’ she said, for her own benefit rather than his. ‘Perhaps I can reject your proposal altogether?’

She could hardly believe she was able to speak such words. That she was actually rewriting a moment from her past. One of the greatest mistakes she had ever made in her life.