If she could get through this door, there was a strong possibility she could get clear away, as she could probably run a lot faster than the two older women. At least, she could have done before she had been starved for a couple of days.

But it wouldn’t be easy to escape with Petal, if she was there. First she had to find her and then, somehow, they’d have to get out without being spotted. The two women weren’t going to give up without a desperate fight: they must know that there would be a long prison sentence for them if Molly managed to get out and fetch the police. She’d already been on the receiving end of one blow to the head, so she could testify to Miss Gribble’s strength.

So the choice was either to flee on her own and get help or to find Petal and, with her, take a chance on outrunning and outwitting the two women.

The first seemed the more practical option, but if the women found out she’d gone they might take Petal and flee. They knew the marshes well and could probably remain hidden for a long time, but what would happen to Petal in that time?

Cassie’s heart told her that she had to find Petal and leave with her. If she was in this house, she’d been through enough. She deserved to be rescued by someone who loved her.

Gingerly, Molly turned the door knob, not for one moment thinking it would just open. But, to her shock, it did. Presumably, the two women had forgotten to lock it, or maybe they’d thought that, if she wasn’t already dead, she had no chance of getting out of the cellar room.

‘Well, I’ve got news for you two,’ she murmured to herself, opening the door just a crack. She could see she was in the hall: it had gloomy, dark, varnished wainscoting with dark-green wallpaper above it. Opposite the cellar door was a mahogany demilune table with a huge, hideous brass eagle perched on a fake log.

She could only see the kitchen doorway and about a foot into the room, but she could hear both women. It sounded as if one of them was chopping something on the table and the other was walking about. Molly opened the door a bit wider, and now she could see it was Miss Gribble chopping vegetables at the table and Christabel pacing around.

Then she had to pull the door almost shut, because if either of them looked her way they would see it was open.

‘Oh Christabel, do stop stalking around like that!’ Miss Gribble snapped. ‘I don’t know what’s got into you today.’

‘She won’t talk to me. She cowers away from me,’ Christabel burst out.

‘I told you right at the start that a child of that age remembers too much about her mother,’ Miss Gribble said impatiently. ‘Anyway, I think she’s half-witted.’

Molly seethed at that insult. It was all she could do not to charge into the kitchen and lay into both women.

‘Come into the garden with me. It’s lovely out there today, and I’ll push you on the swing. That always calms you down,’ Miss Gribble said.

At that, Molly’s eyes widened in shock. They had stolen a child and one was suggesting she pushed the other on a swing to calm her down! Were they both completely mad?

But, mad or not, it was the opportunity Molly had been waiting for. She listened to the women’s footsteps receding and opened the cellar door far enough to see the women go out the back door and into the garden.

She came out into the hall, shut the cellar door behind her and turned right towards the front of the house and the staircase, which she expected to be facing the front door. It was, in a central position, with a further two closed doors to the right and left of it across the hall. The staircase was polished dark oak, large and imposing, with a narrow, almost threadbare carpet runner on the treads fixed in place by brass stair rods.

Molly went up the stairs like the wind, not stopping at the bedrooms on the first floor, because she guessed they’d put Petal in an attic room.

The narrow staircase leading to the attic was bare wood, and food and drink had been slopped on it. A glance out of a back window revealed Christabel sitting on a swing hung on a big oak tree, and Miss Gribble pushing her.

As fast as she could, Molly ran up the last few stairs. ‘Petal!’ she called.

There were four doors up here, but she expected Petal would be in one of the two back rooms. She heard a scuffle, little more noise than a mouse would make, from the second of those rooms. The door was locked and there was no key.

‘Petal,’ she whispered at the door. ‘It’s Auntie Molly come to get you. This door is locked and I need to break it down. Stand away from it.’

The only reply was a little whimper.

Molly didn’t even stop to think of what injury she might do to herself but took a few steps back and then charged into the top door panel with her shoulder. It cracked, and so she did it again. This time it caved right in, and there was little Petal standing there, eyes swollen with crying, thin and very dirty, in a smocked dress which was several sizes too big for her and almost reached the floor.

She looked dazed and unbelievingly at Molly.

‘You’ll have to jump up and wriggle through this hole,’ Molly told her. ‘Come on, be quick! They’re out in the garden, but they might have heard me break the door.’

Petal came through the hole as quickly and smoothly as a cat and threw herself into Molly’s arms, her arms tightly around her rescuer’s neck.

‘We’ll talk later,’ Molly whispered, kissing the child’s head and trying not to cry with joy at finding her alive. ‘For now, we’ve got to be fast and silent. Can you do that?’

Petal nodded, perhaps too overcome by shock to speak.

Molly picked Petal up to hold her on her hip and crept down the staircase. She could see the front door was, as she had expected, locked and bolted. The chances were she’d be struggling with it for too long and they’d be caught.

When she’d glanced out at the garden, she’d seen that the swing was about twenty-five yards from the kitchen door and, if she remembered rightly, there were bushes between them which would shield her and Petal from view. She hoped they’d have enough time to run round the house, down the drive and away.

They had just reached the hall when, to her horror, Miss Gribble appeared. Molly’s blood ran cold, because she had a long poker in her hands and, judging by the ferocious look on her face, she’d heard the door being broken and had every intention of using her weapon.

Molly shook with fear. There was no doubt in her mind that this woman would think nothing of killing both her and Petal. She jabbed out with the poker at Molly, and Petal squealed and clung more tightly to her.

‘I should have dealt with you when you first got here, but I will now, and that brat!’ the woman snarled at her. She had big, yellow teeth like a savage animal.

‘Please let us go,’ Molly said. She knew that nothing she said would make any difference, but she hoped the woman would think she was docile and stupid enough to allow her to prod them down the hall and back towards the cellar.

The big brass eagle would make a good weapon if Molly could reach it and, even if Christabel appeared, Molly had the idea she was a bit thick, so Petal could probably run past her. ‘I told loads of people I was coming here, so the police will be here before long,’ she said, playing for time. ‘But if you let us go now, I’ll tell everyone I found Petal out on the road.’

‘Save your breath. You won’t have it for long!’ the woman roared at her. It was as if she was possessed: her eyes were rolling and she had spittle coming out of her mouth. She was lifting the poker up above her head ready to whack Molly with it.

Molly put her lips close to Petal’s ear. ‘Run when I put you down. Get help,’ she whispered.

Petal made a little grunt, which appeared to indicate that she’d understood, and as Molly jumped to one side as the poker came down to hit her, she let Petal drop to the floor.