The next time Jimmy went to the lake the crocodile was nowhere to be seen. As usual, he called, and rustled the paper bag – he’d brought fruitcake, this time. Then he waited, watching a family of ducks trailing across the water in an unruly line and listening to the pigeons cooing in the woods behind him. It was a perfect day, with little clouds scudding across a deep-blue sky, reflected on the still surface of the water below.

At last she appeared, or at least he thought it was her. To be honest he wasn’t sure at first, because she looked so different. In the few days since he’d last seen her, her legs seemed to have grown, her tail was long and curly and on her back, either side of the lumpy ridge, were two new humps.

‘Whatever’s happened to you . . .?’ he began to ask, but he was stopped mid-sentence by the most astonishing sight. She grunted once or twice, and the humps on her back started to unfurl into wide, ribbed sheets of tough, green hide. With a powerful movement of her shoulder blades she began to flap them, up and down, and as she did so they grew higher and wider still.

‘Oh . . . my . . . goodness,’ he managed to gasp. ‘You’ve got wings.’

‘Like a proper dragon,’ she said, grinning widely, and flapping so enthusiastically he feared she might blow him off his feet. ‘And there’s something else, Jimmy. Better move away, just in case.’

He scuttled backwards until there were five or six yards between them.

‘That’ll do.’ She sucked in an enormous breath and then let it out with a loud whoosh that turned into a bright red-and-orange flame, smelling of wood fires and toffee caramel.

Jimmy burst into astonished laughter and she laughed along with him, with a deep fearsome roar. Each time he tried to stop she flapped her wings again, whipping up dead leaves and bits of grass into a great whirlwind, which made him laugh all the more. At last he got so out of breath that he had to sit down, and she noticed the brown paper bag.

‘Have you brought buns?’ she asked, folding away her wings. ‘All that flapping is hungry work.’

‘Fruitcake, with marzipan and icing. You’ll like it,’ he said, passing her a slice.

‘Yum, this is delicious. I’ll miss you, you know,’ she said, through a mouthful.

‘Miss me? Why? Where are you going?’

‘Now I’ve turned into a proper dragon I’m in too much danger, living near human beings. They’d shoot me down like one of those poor pheasants. I have to go and live in Dragon Land, where I will be with others like me, and they will keep me safe.’

‘You can’t,’ he said, close to tears. ‘You mustn’t leave me.’

‘I have to, Jimmy.’

‘Can’t I come with you?’