– But let’s not talk about her. How’re you?

No! It’s her I want to talk about.

– Good, I say.

A moment later he replies:

– I’m Lukas. Fancy a chat?

I stop. Since I’ve been going online I’ve learned it’s unusual for someone to give away their name so quickly. I wonder if he’s lying.

– I’m Jayne.

I pause.

– Where are you?

– In Milan. How about you?

I think of his first message. You remind me of someone.

I want to find out if he might’ve talked to Kate. I decide to tell a lie of my own.

– I’m in Paris.

– A beautiful place!

– How do you know the city?

– I work there. Occasionally.

My skin prickles with sweat. I try to take a breath but there’s no oxygen in the room.

Could he have chatted to my sister, even met her? Could it be him who killed her? It seems unlikely; he looks too innocent, too trustworthy. Yet I know I’m basing that impression on nothing, just a feeling, and feelings can be misleading.

What to do? I’m shaking, I can’t take in any air. I want to end the chat, but then I’ll never know.

– Really? I say. How often?

– Oh, not that often. A couple of times a year.

I want to ask if he was there in February, but I can’t risk it. I have to be careful. If he did know Kate and has something to hide then he might work out I’m on to him.

I have to keep this light, breezy. If things become sexual there’ll be no way of finding anything out, nothing I can do but end the conversation as quickly as possible. I want to look for clues, but I can’t let things tip over.

– Where do you stay when you’re over here?

I wait. A message flashes. I can’t decide whether I want him to tell me he has a flat in the nineteenth, or that his office put him up in a hotel near Ourcq Métro, or not. If they do and he does, then it’s him. I’m sure of it. Hugh and I can tell the police what I’ve found. I can move on.

But if he doesn’t? What then? I still won’t know.

His message arrives.

– I’m not there often. I tend to stay in hotels.

– Where?

– It varies. Usually pretty central. Or else I stay near Gare du Nord.

I don’t need to pull up a map of Paris to know that Gare du Nord is nowhere near the area Kate’s body was found. I’m curiously relieved.

– Why do you ask?

– No reason.

– You think maybe it’s near you?

He’s added a smiley face. I wonder if the flirting has moved to the next level. Part of me wants to end it, but another part of me doesn’t. He might be lying.

I hesitate for a moment, then type:

– I’m in the north-east. The nearest Métro is Ourcq.

It’s a risk. If it’s him he’ll know I’m linked to Kate. It can’t be a coincidence.

But what will he do? Just end the conversation, log off? Or would he stick around to try and find out exactly what I know? It occurs to me he might already have guessed who I am and why I’m chatting to him. He might’ve worked it out from the start.

I press send, then wait. Largos86 is typing. Time stretches; it seems to take for ever.

– Is it a nice area?

– It’s okay. You don’t know it?

– No. Should I?

– Not necessarily.

– So are you up to much? Have you had a good day today?

I hesitate. Last time, at this point, I was being asked what I was wearing, or whether I’d like fantasy role play or straight cyber. It’s a relief that this conversation is unthreatening.

– Not bad, I say.

I wonder why I’m relieved. Is it that in these few brief moments I’m not in mourning?

– Tell me what you’ve been up to.

– You don’t want to hear about me.

– I do. Tell me everything!

– Why don’t you tell me something about you, first?

– Okay, let me think.

He’s added a cartoon, another face. This one looks puzzled. A few moments later his next message arrives.

– Okay. You ready?

– Yes.

– I really adore dogs. And cheesy love songs. The cheesier the better. And I’m really scared of spiders.

I smile. I can’t help it. I look back at his photo. I try to imagine what Kate might’ve thought, looking at him. He’s certainly attractive, and around her age.

His next message arrives.

– Your turn. You owe me two facts.

I run through a list of what I might tell him. I’m looking for something that will draw him out, some fact that might lead him to tell me whether he was in Paris in February, or might have chatted to Kate.

I lean forward and begin to type.

– Okay. My favourite season is winter. I love Paris, in February especially.

I press send and a moment later he replies.

– That’s fact number one.

– And – I begin, but then I freeze. There’s a sound, a key in the lock. The real world is intruding, too loud. It’s Connor, coming home. As he opens the door I’m still adjusting, to the living room in which I’m sitting, to my own home. I switch on the television and the credits roll silently. Connor comes in.

‘Oh, I didn’t know you were in here.’

I close my machine and put it to one side. My heart thuds, as if I’ve been caught taking drugs. He’s wearing a baseball cap I haven’t seen before and a black sweatshirt; he’s chewing gum.

‘What’ve you been up to?’

‘Just studying.’

I force a smile. ‘How’s it going?’

‘Okay. What’re you up to?’

I feel dizzy. It’s as if domesticity is crashing in around me in an inrush of banality, of making meals, of ferrying to school and back, of worrying about what to cook for dinner and whether the surfaces in the kitchen are clean.

I adjust my necklace. ‘Just reading emails.’

He asks for a snack. I make one for him, then he goes upstairs and I go back to my machine. Largos86 is no longer online, so I message Anna.

– He says he’s called Lukas.

– And?

What to say? I have a feeling, a suspicion. Based on what?

– I don’t know. There’s something about him. He seems really keen.

I hesitate, but continue.

– I just wonder if he knew Kate.

– It’s unlikely, don’t you think?

I agree.

– But yes, it is possible he talked to her.

– You think?

– Well, there aren’t that many people who use that site.

– So you think it might be worth talking to him some more?

– Well, don’t get your hopes up. But maybe. We might be able to find out who else Kate was talking to. Or at least prove one way or the other whether he knew her.

The next day I take my laptop into my studio. The same guy is online. Largos86.

– You disappeared, he says. I wondered what I’d done.

It’s his fourth or fifth message. At first I wasn’t sure I’d reply, but they keep coming.

I can’t forget what he’d said. You remind me of someone. Someone I liked a lot.

– I’m sorry, I say.

I resist the urge to make an excuse. I can’t tell him about Connor coming home. It wouldn’t be right. It would take the conversation in the wrong direction. I wonder who’s watching whom. I wonder who’s the cat, and who’s the mouse?

– Are you alone?

I hesitate. Connor’s in the house, doing his homework, he said, and Hugh’s out at a concert with a friend, so I might as well be. I certainly feel alone.

Plus, I’ve realized I’m going to have to give something if I’m going to get something back.

– Yes. Yes I am.

A moment later his message appears:

– I enjoyed chatting to you yesterday …

I wonder if there’s going to be a but …

– Thanks.

– But we never really got on to talking about you.

– What d’you want to know?

– Everything! But maybe start by telling me what it is you do.

I decide I don’t want to tell the truth.

– I’m in the arts. I curate exhibitions.

– Wow! Sounds interesting.

– It can be. So how about you? I know you travel.

– Oh, let’s not talk about me. It’s boring.

Maybe it is, but I’m trying to find out why he’s so keen to chat to me again tonight.