‘Who else was in the photo?’

I still feel uneasy about telling him this part. I wonder if he’ll think I was drunk and did it myself, then lost the picture. That explanation certainly crossed my mind. He takes a step closer. Too close.

‘Anna, if other women might be in danger, I need to know about it.’

‘It’s just a picture from twenty years ago. It might not mean anything. But it’s of me, Rachel Hopkins, Helen Wang, a girl you wouldn’t remember, and…’

‘Who?’

‘Your sister.’

Him

Wednesday 09:30

I call Zoe as soon as Anna has gone.

I watched my ex-wife being driven away by her cameraman, with an uneasy feeling I can’t explain. She looked more vulnerable just now than she has for a long time. Sometimes I forget who she really is, underneath the tough exterior. The version of herself she presents to the rest of the world isn’t the same as the woman who was once my wife.

Zoe seems amused by her older brother’s sudden concern for her safety and wellbeing. I don’t explain why I’m worried, or mention the photo. Instead, I just listen to the familiar sound of her voice, as she insists for the third time that she is safe and that the house is completely secure. I ask her to turn on our parents’ old burglar alarm – I’m fairly sure we are the only two people who know the code – then I do my best to get back to my job. I’ve always been a bit concerned that Zoe’s past might catch up with her one day. My sister got in with the wrong crowd for a while when we were young. I know, because I did too.

It turns out to be another long and tedious morning, consisting of my second trip to the pathologist, new reports to write, lengthy briefings with an inexperienced team, more unanswered questions as well as questions to answer. Along with the worst part of my job; telling a parent that their child is dead. Age is never a factor in the pain that particular news inflicts. Everyone is somebody’s child, no matter how old they are.

‘Who did this?’ asked Helen Wang’s elderly mother, as though she thought I knew the answer.

I sat in her front room, not drinking the Earl Grey tea she insisted on making, or touching the tin of shortbread biscuits open on the table. Her grey hair was cut in the same Cleopatra style as her daughter’s, and her immaculate clothes looked like something a much younger woman would wear. There was no longer a Mr Wang, and she lived alone in an orderly but unremarkable house. She started crying as soon as we arrived, and I think she already knew something was wrong.

I spared her the majority of the details regarding how Helen was found at the school, but I won’t be able to stop her from reading them in the press. She’ll know about the drugs we found at her daughter’s home soon too. I can already imagine the headlines: The Headmistress with a Habit.

I normally let junior detectives inform next of kin, just like I had to when I was working my way up. But I missed knowing about Rachel’s husband, and her mobile phone, when I sent Priya last time. I don’t plan to make the same mistake twice.

I’m instructed by those on higher salaries than my own to give another scripted press statement. Preparing for the performance eats into my afternoon. I choose to do it outside Surrey Police HQ this time, in an attempt to keep journalists away from the school, and although I see Anna standing there amongst the other reporters, she doesn’t ask a single question. When I retreat back inside, someone has turned on the TV in the office – presumably to watch the presser on BBC News – and I see my ex-wife on the screen. It’s as though she is staring right at me.

I don’t know what to say at first when Priya invites me for a drink after work.

‘Thanks, but with Blackdown being the place it is, there’s nowhere we could go without the locals or the media trying to eavesdrop on every word of our conversation.’

‘I did think of that, sir. Perhaps a drink at mine, where it would be more private?’

I don’t know what face I pull, but from her reaction I’m guessing it can’t be good. She starts to speak again before I can form a response, and I dread to think what she might say next.

‘I’m not really inviting you over for you – although you do look like you could do with a drink – it was more for myself, really. This is all a bit… new for me, and I don’t know anyone here. I’m living on my own at the moment, so there’s nobody for me to talk to when I get home. I guess I just didn’t fancy walking into the house alone, after seeing two women brutally murdered. That’s all.’

She stares at me, then examines her short fingernails, as though it is imperative that they are as neat and tidy as the rest of her. Women baffle me on a daily basis. That said, I do feel a smidgen of guilt. Priya is alone in a town where the locals aren’t always friendly to new faces. It isn’t as though I have anyone to rush home to either.

I weigh up my options and conclude that my colleague needs me more than my sister. Even though a nagging voice in my head tells me I should go home and check on Zoe, a louder one tells me not to. She’s always been able to take care of herself. Besides, all we ever do when we’re together is argue about money, or what to watch on Netflix. It’s not so different to when we fought over toys or the remote control as children. I’m sure Zoe would rather have the place to herself for the evening. Accepting Priya’s invitation would just mean having a friendly drink with a colleague; a perfectly normal and innocent thing to do. The right thing to do.

One hour and two beers later, Priya is cooking homemade burgers and sweet potato fries. Her house is on the edge of town. It’s a new-build – one of those estates where the houses are on top of one another and all look the same, with red brick walls and PVC windows – but it’s nice enough. Rented, of course, but decked out in stylish furniture, and painted in a series of inoffensive neutral colours.

Everything is spotlessly clean, with low lighting and zero clutter. I note the lack of family photos, or anything remotely personal. If I’d ever given any thought to Priya’s home before now – which I hadn’t – I think I might have predicted Ikea or chintz, but I would have been wrong. Everything I thought I knew about her seems to have been a little off base. The only thing that looked out of place was my scruffy jacket when she hung it on the fancy-looking coat rack, and my shoes, which I took off in the hall. I was slightly paranoid that she might notice they were a size ten.

‘I just need to pop out for something I forgot,’ she says, handing me another beer. ‘Make yourself at home and I’ll be back in a jiffy.’

The expression sounds too old for her young voice, and it seems strange to leave me alone in her house. She turns on the small TV in the kitchen to entertain me, and I drink another beer while watching my ex on the BBC News channel. I’m unable to tell if Anna is live this time, or whether this is just a repeat of what she said earlier.

I do something stupid then. I don’t know whether it’s the beer, or the tiredness, or frankly whether I’m just losing my mind, but I switch on Rachel’s phone. I cancelled the trace on it this afternoon – being in charge does have some benefits – and I need to know how her mobile got in my car. Feeling like someone is watching me and trying to set me up is starting to take its toll.