Eventually, if she didn’t turn up, Mrs Bridgenorth would alert the police. They would contact Charley, and when he told them she’d been determined to find Cassie’s mother and thought she lived in a nearby village, the police might end up here.

But how long would that take? At the very least, it would be days. The thought of spending even one night in such a cold, damp place without food, water or a blanket was terrifying.

The cold floor was striking up through her skirt to her bottom now, and the light coming through the small window was fading. She had to make a plan for when total darkness fell.

Getting to her feet, she went over to the workbench. The top of it was wood – far warmer to sit or lie on than the floor. She pushed the apple boxes to one side and found a piece of rag. She wiped the dust off the bench, then pushed all the crates away, hoping to find anything – rags or sacks – to keep her a bit warmer, or a tool to pick at the door lock. But there was nothing.

She prowled round the cellar then, looking for anything useful, but there was nothing other than cobwebs.

She picked up a crate, intending to start banging on the door again, and something dropped to the floor with a slight tinkle. She couldn’t see what it was, as the light was so bad, but she groped around with her hand and eventually found it.

It was a hair slide – just a little red circle like a Polo mint, with a metal clasp across the back. It looked familiar, but maybe that was just because she had worn such hair slides when she was little.

Grabbing a box, she began to bang and shout again. It made her feel warmer, even if it did no good. She thought she would do it in the middle of the night, too; with luck, it might annoy them so much they would come down.

Once complete darkness fell, Molly was unable to maintain her calm. She wanted to relieve herself; she was cold, hungry and thirsty, and very frightened. It seemed to her as she lay hunched up on the workbench that if a person could knock you out and drag you to a cellar, they were capable of leaving you there for ever. Compared with that, her fear of spiders seemed silly, but still she kept imagining them creeping towards her in the dark.

She couldn’t see her wristwatch now, but it couldn’t be more than nine at night, as it hadn’t been dark for that long. She wished she could fall asleep, but it was too cold for that.

She thought of Constance and how much she’d believed in the power of prayer.

‘Not a sparrow can fall from its nest without Him knowing,’ she’d said, on many an occasion.

‘If you know about the sparrows, what about me?’ Molly asked God. ‘I haven’t done anything bad, I was trying to put things right, so please help me. Make someone work out where I am.’

All at once, almost as if God had heard her prayer, she remembered why the red hair slide looked familiar. Petal had always worn two of them in her hair, one on either side.

It could, of course, be pure coincidence that a hair slide like Petal’s had been dropped here. But she didn’t believe it was. She just knew Petal had been here.

At four o’clock in the morning, while Molly was shivering uncontrollably and thinking she just might die of it, Evelyn Bridgenorth was lying awake, worrying. She had stayed up till after twelve in the hope that Molly would turn up or telephone, then, as all the guests were now in bed, she finally locked the hotel door and went up herself.

Ted was already asleep, and she didn’t want to disturb him by putting the light on and reading. So she just lay there, waiting for sleep to overtake her, but it didn’t; her mind was racing too fast.

She heard the church clock strike four and wondered how she was going to run the hotel when she’d had no sleep. If Molly did come breezing in the next morning, she’d get a real tongue-lashing for putting her through this.

At ten o’clock Evelyn Bridgenorth rang the police station to report Molly missing.

‘It’s not unusual for young women to just take off,’ the sergeant said, clearly not having taken on board what she’d just said about Molly being a reliable and conscientious girl. ‘It’ll be a man, I expect. He’ll have sweet-talked her into dropping everything and, when she comes back, she’ll tell you a cock-and-bull story that she was on an errand of mercy.’

‘Miss Heywood left on a bicycle. She took no clothes or overnight things. She didn’t even have a coat with her,’ Evelyn said crisply.

‘Oh, we’ve had plenty of women go missing when they said they were just out to buy a pint of milk and still wearing their pinny. No accounting for what goes on in women’s minds.’

Evelyn was tempted to tell him that she was imagining going down to the police station and throwing the contents of a chip pan over him. ‘I want you to look into it,’ she said through gritted teeth.

‘Tell you what, Mrs Bridgenorth, as it’s you, if she isn’t back in two days, I’ll see what I can do.’

‘You don’t suppose Molly’s disappearance has got anything to do with her looking for her friend’s family?’ Ernest asked Mrs Bridgenorth that evening when he opened the bar. ‘She hadn’t given up on finding them. I’ve heard she’s been asking around the town about the family quite recently.’

‘Yes, I know about that. Ted told me. But I can’t see that there’d be any connection between that and her disappearance. I mean, her friend was killed back in Somerset.’

‘Maybe so, but if the dead girl’s family live around here, Molly may have stumbled into something they want kept hidden,’ he said. ‘What are you going to do?’

‘I’m going to call the police.’

‘But I thought they wouldn’t do anything.’

‘Not the Rye police – they’re a bunch of disbelieving idiots. If she isn’t back tonight, I’m going to call Molly’s policeman friend in Somerset and hear what he has to say. I’m also going to ring her friend Dilys and see if she knows anything.’

Molly was beyond crying now that darkness had fallen for a second night. The previous night had been long and tortuous, and the daylight hours that followed it almost as bad. Every now and then she had banged on the door and screamed, but it was no use. Now she was so hungry and thirsty she could think of little else but food and drink, and the cold made it impossible to fall asleep and forget about it for a few hours.

She now knew without a doubt that she’d been left here to die. Maybe when the two women had dragged her here unconscious, they thought she was already dead. In any case, the fact they hadn’t been back to check on her proved that was what they wanted.

Yet, however utterly miserable she felt, Molly’s mind was still active, and it seemed to her that no one would react quite as aggressively as those two women had unless they had something very serious to hide. She felt certain now it was they who had attacked Cassie, and taken Petal.

When she’d walked around the back of Mulberry House Molly hadn’t really noticed much beyond the garden being overgrown. Yet out of the corner of her eye she was sure she had seen a black car, an old Austin or something similar. The two women could have found out where Cassie was living and driven to Somerset.

She asked herself what would have made them attack Cassie. Surely a mother would only drive all that way out of love, wanting to be reunited with her daughter? Maybe Cassie hadn’t been able to forgive her for turning her back on her when Petal was born, and had told them to leave. Perhaps a fight had broken out because Cassie had told some home truths, and one of the women had hit her so hard that she had fallen on the hearth. Then, perhaps, realizing Cassie was dead, they had taken Petal with them so she couldn’t tell anyone what had happened.

What had they done with the child? That was the most important question now.

Having seen how they lived, and how irrational and volatile they were, they could well have killed her. With miles and miles of marshland within a stone’s throw of the house, they could have buried her little body anywhere and no one would ever find it. That would explain their panic when she’d arrived.