His mother was very concerned when he gave her the letter and told her the gist of what was in it.

Janet Walsh was a typical countrywoman: plain, strong, hardworking and no-nonsense. She had always liked Molly Heywood; indeed, she had once or twice admitted that she’d always hoped that one day George would marry her. But she was very aware that, because George was a mere constable, his superiors would take a dim view of him riding off to rescue a girl he went to school with, just because he thought she was in trouble. That is, of course, if she was in trouble. For all Janet knew, and George, too, for that matter, she might have run off with some sweet-talking man.

‘Now, son, this is madness,’ she said, shaking her head. ‘Why can’t you let the police down there investigate it?’

‘Because I could sense that something bad had happened to her the moment her boss told me she was missing. I’ve got three days’ leave, Mum, and how I spend it is my business. I couldn’t live with myself if Molly was killed while I sat on my hands, along with the local police force.’

‘Why should she have been killed, George? Aren’t you being a bit melodramatic?’

‘Cassie was killed, remember,’ he replied. ‘And Petal was taken away, Heaven knows where. If these two women were responsible for that, they wouldn’t have liked Molly turning up, would they?’

‘No, I suppose not.’ Mrs Walsh sighed. ‘But now you’ve given me something more to worry about.’

‘If you give that note to Sergeant Bailey a couple of hours after I’ve left, he’ll make sure there’s back-up down there. Now, please would you make me a couple of sandwiches and a flask of tea to take with me. It’s a long ride.’

‘You aren’t thinking of going all that way on your motorbike, are you?’ His mother’s voice rose in horror. ‘I thought you’d be going on the train.’

‘The bike is much quicker,’ he said. ‘There’s no direct train to Rye.’

He got together a few bits and pieces he thought he might need, including a map, a toothbrush and a change of clothing, a jemmy, a screwdriver and a bolt cutter, and put them into the pannier on his motorbike, then went in to put on his leathers.

When he came back downstairs his mother met him in the hall and handed him a sandwich box and his flask.

‘Drive carefully, son,’ she warned him. ‘Ring us when you get a chance. I’ll be praying you find Molly unharmed.’

‘You’d better tell her mum about this,’ George said reluctantly, as he put on his helmet. ‘She needs to be prepared, just in case.’

‘The poor woman.’ Mrs Walsh sighed. ‘Her husband’s such a miserable devil, and now both her girls gone and unlikely ever to return. And now this. It’s enough to crack her.’

‘I know you’ll do a good, diplomatic job,’ George said. He could see by the way his mother was biting her lower lip that she wasn’t far off tears. ‘Now, don’t go worrying about me. I’m a grown man.’

She shook her head and half smiled. ‘Not to me you aren’t,’ she said, then, taking a step closer to him, she patted his cheek. ‘But you are a brave, gallant one, and that makes me proud.’

It was around eleven thirty when George rode out of Sawbridge, and within the hour he was riding over Salisbury Plain, towards the south coast. It was no hardship to him to go such a long way on his bike. Under happier circumstances, he’d have loved it, as he rarely got to ride long distances. Thankfully, the splattering of rain that had been falling when he set out stopped soon after he bypassed Bath, and now the sun had come out.

‘I’m on my way, Molly,’ he murmured to himself. ‘Just hang on, and don’t do anything reckless.’

Molly had been busying herself from first light trying to find a long nail in one of the boxes. In over three hours she had only managed to gouge out three nails, and they were all short ones. But then she spotted one with a far larger head, which suggested it would be longer, and she worked and worked on it with the aid of one of the others.

It had rained quite hard in the night, and she’d stretched up and held out her shoe to try and collect some rainwater in it. She got about half a cupful, and nothing had ever tasted better, even if it was tainted with the smell of leather. Then the rain eased off to just drizzle and she couldn’t hold her arm out long enough to collect more than a few drops.

But it was something: just that small amount of water had made her feel a bit better and, without it, she doubted she’d have been able to stick at trying to get the nails out.

Her fingers were sore now, and she had several splinters, but when she finally drew out the nail and found it was one and a half inches long, and thick, she felt triumphant.

Picking locks always looked simple in films, but it didn’t turn out to be. She pushed the nail this way and that, but the mechanism didn’t move. After an hour working at it she’d had enough; she was dizzy and she had cramps in her stomach. In a moment of frustration she shoved a thin, wedged-shaped piece of wood from one of the boxes into the keyhole and banged it in with her shoe. To her surprise, she heard a dull click.

She couldn’t really believe she’d somehow managed to unlock the door, and when she tried to turn the knob she fully expected it would stay put. But, to her delight, it turned. She’d got the door open!

Her instinct was to just rush out, but she forced herself to take some deep breaths, to put her shoe back on, despite it being wet, and to gather her thoughts.

It must be around midday. The two women were bound to be in the house and she had no idea of its layout, not even whether the front door would be on her right or her left. She knew that, in most houses, the cellar was reached via a door in the hall or the kitchen, and that that door was likely to be locked, too.

Peeping through the open door, she found that there was some light in the cellar corridor because the other three rooms down there all had their doors open. The one opposite had a small, barred window like the one in the room she was being held in. When she crept out, she saw that the remaining two rooms were much the same, one a small store room for preserves. It was very tempting to grab a jar of plums or gooseberries to eat, but getting out was her priority.

The other two rooms held nothing but a few sticks of old furniture, and she passed on quickly to the stone staircase at the end of the corridor. She crept up it and paused to listen before trying the door.

To her right there was the sound of running water and a clattering of dishes, so she guessed that it had to be the kitchen and that someone, or perhaps both women, was in there.

That meant the front door would be to her left. But, as country people rarely used their front door and normally locked and bolted it, she didn’t think she should rely on that door. Even supposing the keys had been left in it, it might be swollen through lack of use and she could waste valuable time trying to get it open.

She continued to listen carefully and, just as she was almost giving up on hearing anyone speak, Miss Gribble did. She said something about needing to use up the stew.

Christabel responded, ‘She won’t eat that.’

‘If she doesn’t, she can go hungry,’ Miss Gribble said sharply.

Molly was crouching down on the stairs, her ear to the keyhole. She was so hungry she felt she would eat a boiled cat if it were offered to her, but the conversation she’d just overheard made her forget her hunger: it was evidence to her that Petal was not just alive but in this house.

She forced herself to stay still and think about it. They might not be talking about Petal, of course; the person who wouldn’t eat the stew could be a friend or a relative. She mustn’t go charging about half cocked. She needed a plan.

Yet the thought that little Petal could be alive and in this very house made her pulse race.