After the recording ended, they sat in shocked, frozen silence for a few minutes. Rain tapped sharply at the window, like someone with skeletal fingers asking to be let in. The laptop's screen dimmed and then went into sleep mode. At last, Barbara spoke.

"That was him, wasn't it? That's what he sounds like."

"Yes," Alison said.

"He's evil," Barbara said. Her voice quivered as if she were about to cry, but when Alison twisted round in her arms to look, there were no tears: her eyes were wide and scared and very dark, with pupils dilated almost far enough to swallow up the irises, but they were dry. "I thought he was psychotic, and he probably is that too, but –" She shuddered and let Alison go. "You were right. It's both. It's madness and evil, and I can't tell where one leaves off and the other begins."

"I know," Alison said. "But don't think about that just now. Think about Paul instead. He's on the opposite side; he's fighting for good, and he needs you to help him. What did he mean when he told you to go home?"

"I've no idea," Barbara said. "He couldn't have meant for me to go home to my house; all he's done so far has been to try to warn me away from there. And as for getting something –" She made a helpless palms-up gesture. "I have a few books and vinyl records that belonged to him, and I think my brother Stephen has the watch he got for his eighteenth birthday, but everything else has been gone for years and years. Our parents gave all his clothes and things away because they couldn't bear to look at them. And even if I could get them, I don't see what good they could possibly do."

"We'll work that bit out later," Alison said. "Where else is home?"

"Erm, the only other place would be the house we grew up in. That would be home to Paul; he never lived anywhere else, except for the few months he was away at uni."

"Who owns that house now?"

"My mother does," said Barbara. "She lives in it. We've tried to get her to move into a smaller place, Stephen and I, but she won't hear of it."

"I reckon stubbornness runs in the family," said Alison with a wry smile. "All right. Is anything still there, in that house, that would have been special to you or to Paul, or to both of you? He obviously thought you would know."

Barbara shook her head, at a loss. "As I said, all of Paul's things are long gone, and I doubt there's anything of mine there either, unless my mum has my roller skates or my Sindy doll stuffed up in the loft. And don't forget, Paul was the eldest by six years; we didn't begin to have a more equal relationship until near the end of his life, when we were both teenagers. What I mean is, I told him my secrets, but he didn't often tell me his. If he had some sort of a – a talisman, I didn't know about it. I swear."

The look on her face was so genuinely baffled that Alison concluded she was telling the truth. Frustrated, she stretched out amongst the cushions on the floor and lay flat on her back, hands over her face, trying to think. For at least the hundredth time in the past few days, she wished she could talk to Helen, or to her Aunty Vi, either of whom would have known what other questions to ask to tease out the right answer. Although if she had to try spirit travelling after all, she thought, she might be seeing Vi sooner rather than later. Drained and injured as she was, how much chance would she have of making the journey safely?

It was an upsetting prospect, but she had forgotten that Barbara was blessed with both an agile mind and an obstinate refusal to give up on a problem. Barbara had kept mulling over the question while Alison was lost in worry, and now she presented a possible solution.

"There's the summerhouse," she said, "but that's a place, not a thing I can fetch."

Alison parted her fingers just enough to look up at Barbara through them.

"What summerhouse?"

"The summerhouse in our garden," Barbara said. "That was something important to both of us."

"It was?" Alison asked, sitting up again. On her bedside table, she caught sight of Barbara's discarded glass, with a mouthful or two of wine still left at the bottom, and felt a wave of craving so overwhelming it frightened her. She deliberately averted her gaze and focused on Barbara's face, marred by fatigue and dark, puffy circles under the eyes, but still possessing the sort of ageless bone structure that made artists weep.

"Tell me about it," she said.

"Well, it was built around the same time as the main house, but the previous owners had let it go to rack and ruin, and it was just an eyesore really. My dad was always saying he was going to pull it down, but he never did, so it became a dumping ground for boxes and tools and broken things, not to mention a sanctuary for mice." She grimaced. "No one wanted anything to do with it, so when Paul was fifteen or sixteen, he cleared out a lot of the old rubbish and turned it into his own private place, where he could go to get away from the rest of the family. For a long time, he wouldn't let anyone else near it, but the last year he was at home, he started inviting me in to visit. We would listen to the radio, or sit and talk, and I was so proud to be grown-up enough to spend time with him that way – not as a little sister who needed looking after, but as a friend ..."

Barbara trailed off, and Alison saw that this was a painful memory as well as a sweet one, full of wistfulness for the relationship that might have been, if they'd only had the chance to know one another as adults. She wasn't sure whether it made her wish she'd had a brother of her own, or feel relieved that she'd never had one to lose.

"Anyway," Barbara went on after a pause, "just before he left to go to uni, he took me and Stephen out into the garden, and he stood us in front of the summerhouse and announced that as I was next eldest – I was thirteen then, almost fourteen, and Stephen was eleven – he was passing it down to me, and if Stephen so much as put a foot over the threshold without my permission, then he, Paul, would personally give him a good smacking next time he was at home. So it became my place, and after Paul was killed a few months later, I spent lots of time there, reading his books and thinking about him, and sometimes talking out loud to him as if he could hear me."

"He did hear you," Alison said.

"Yes," Barbara said, as if realising it for the first time. "I suppose he did, didn't he?"

There was another silence, but not an awkward one. Then Alison said, "So the summerhouse is still there, then?"

Barbara nodded. "When I went to uni myself, Stephen used it for a couple of years, and then he left home too and it slowly became a storage shed again. The last time I looked inside was two or three summers ago, when I was visiting, and it was crammed full of old furniture. Certainly nothing that seemed to have any sentimental value - but it's the only place or thing I can think of that would have meaning both to me and Paul. He never said it in so many words, but I know he enjoyed the time we spent together there, too."

"All right," Alison said, "we've got to go and see what we can find. Where is it?"

"You won't like this," Barbara said, "but it's where we've just come from. We could have got there in five minutes from that damned graveyard. If we'd known ..." She shrugged. "There's no help for it now. We'll have to go back, that's all."

"We ought to leave soon, then."

"Not today," Barbara said firmly. "I know time is short, but my mother's nearly eighty and not in the best of health, and I don't mean to worry her with any of this if I can help it. Her social club meets every Monday and Wednesday morning, so we can go first thing tomorrow, while she's away. They play euchre for money and it goes on for hours; we'll be gone long before she comes home." She stood up. "I shouldn't impose on you for another night, though. I can find someplace else to stay."

"You aren't imposing," Alison said. "Actually, I - I'd like you to stay here. It's nice to have company now and then, and you're a good guest."

Barbara had been looking a bit stiff and haughty, as Alison had realised she often did when she was feeling uncomfortable or unsure of herself. Now she relaxed into a smile, a real, warm one that crinkled the corners of her eyes and transformed her whole face. "Okay. Thanks."

"It's nothing."

"No, it isn't." Barbara said. She brightened with a sudden idea. "Suppose I cook a real dinner for you, as a sort of repayment? I could do that steak you didn't have at the hotel the other night."

"You don't have to."

"But I want to."

Alison bit her lip and then yielded, partly to humour Barbara and partly because she couldn't remember the last time she'd eaten steak - or any sort of protein that wasn't either cheap mince or suspicious chicken parts on the verge of expiring - and the thought made her mouth water. So did the idea of having her daily glass of wine along with it; but that, she thought, was a concern for later.

"That sounds lovely," she said.

"Good," Barbara said, pleased. "I'll go shopping right now."

"Take your time," Alison said. "I've got something to do, and I've got to do it alone."