The three familiar faces with the red ‘X’ over them didn’t belong to the killer’s three victims. They belonged to the people who the killer had called – Tanya Kaitlin, John Jenkinson and Erica Barnes. They had been the real targets of the ‘video-call killer’.

‘Innocent?’ Holden asked, his tone almost sarcastic. ‘Have you looked at the pictures at the top of each column?’

‘I have,’ Hunter confessed.

‘And can’t you see what they’re doing?’ Holden’s voice was still calm, but Hunter could tell that anger was starting to creep into it.

‘Yes, I can.’

The accident Hunter had read about back in his office was the connecting link between Holden and his targets . . . his victims. It was the reason behind all his torturing. The reason behind all his murders.

The accident had happened three and a half years ago in Lancaster, Northern Los Angeles. At around two in the morning, on Sierra Highway – a single-carriageway road that links Los Angeles to Mojave – a blue Ford Fusion driving south crossed over on to the north-heading traffic and collided head-on with a white Saturn S. Both occupants of the Ford Fusion, a couple in their early twenties, died instantly. The Saturn S was carrying a family of four: Nicholas Holden; his wife of ten years, Dora; and both of their daughters, nine-year-old Julie and Megan, seven and a half. Nicholas Holden was the only survivor of that tragic collision.

Back in his office, Hunter had had no trouble accessing the report by the Collision Investigation Unit. The conclusion reached by the investigating detective had been that the accident took place because the driver of the Ford Fusion had diverted her attention off the road. The reason for that, as witnessed by the driver of another car, was that she had been using her cellphone to take a selfie with her boyfriend while the vehicle was moving at speed.

That was the recurring theme on all the photographs on Holden’s board – a selfie taken with either friends or family while the subject was driving.

In Tanya Kaitlin’s photo, which was the same photo Hunter had come across back in his office, she and Karen Ward had big bright smiles on their faces while Tanya held her cellphone at arm’s length. The motion blur that could be seen through the passenger’s window left no doubt that the car was moving.

A similar photo had been taken by Mr. J. His wife Cassandra was sitting on the passenger seat, smiling. Their son Patrick was giving them both bunny ears with his fingers from the back seat.

Erica Barnes and her sister, Dr. Gwen Barnes, were both making silly faces at the camera while Erica, the driver, took the shot.

‘Did you know that one in every four traffic accidents in the USA is caused as a consequence of a driver using a cellphone?’ Holden’s voice got angrier. ‘One in every four, Detective.’

Hunter knew the statistic, but he remained silent. His arms were starting to tire.

‘I lost my entire family that night,’ Holden continued. ‘My wife, who was thirty-six, and my two daughters. The oldest was nine years old. The youngest, seven. They all died because some stupid woman decided to snap a selfie while driving down a highway, so she could upload it to her goddamn Facebook page. Now is that fair?’

Another piece of the puzzle just slotted into place – social-media websites. That was the reason he searched them.

‘I too lost my life that night, Detective,’ Holden said. The anger was gone from his voice. ‘One moment I had everything to live for – a beautiful wife and two gorgeous daughters – the next . . . all gone. My life was left without meaning. My heart had nothing to beat for anymore.’

Another heavy pause.

‘After the accident,’ Holden continued, ‘I spent six months in hospital then another year just . . . existing . . . vegetating in this world, really. Everything I did, I did robotically, without any meaning. For me, life became nothing more than a vacuum.’

Hunter noticed that Holden’s voice had moved again. This time, slightly to the right.

‘Despite all the counseling I was given, nothing seemed able to stop the destructive thoughts that tormented me almost daily. Not towards others, but towards myself. Without my family, it didn’t seem like I belonged in this world anymore. But isn’t life ironic, Detective? When I was finally about to succumb to those destructive thoughts, when I had finally decided that I just couldn’t vegetate any longer, I witnessed something that changed my life. As I was sitting at a coffee shop, wondering about the best way to go, I saw a car take out a mother holding a child at a crosswalk. The accident happened because the driver was distracted. Want to have a guess why?’

Hunter didn’t need to reply.

‘That’s right. He was on his fucking cellphone.’

Holden delivered his last sentence with so much anger, Hunter thought he was about to pull the trigger.

‘The mother survived. The child didn’t. The driver never stopped to help.’

The pause that followed was long.

‘What I saw that day, the way it made me feel, ignited something new inside of me.’ Holden’s voice was back to sounding emotionless. ‘That was when it dawned on me that I indeed needed to stop vegetating. Not because I needed to end it all, but because I needed to start living again and I had finally found something to live for.’

‘So you started planning,’ Hunter said, filling in the blanks.

‘So I started planning,’ Holden confirmed. ‘Getting back to work was easy. My counselor had been pushing me to do it for months. As she had always said – the best thing for me would be to keep busy, to keep my brain occupied. Sitting at home all day would undoubtedly force my mind to wander and, in the state I was in, that wasn’t a good thing. I’d probably be digging through memories of the accident or, even worse, harvesting destructive thoughts, which, without her knowledge, I’d been doing since my family’s funeral. So when I finally agreed, saying that she was right, that keeping busy and returning to work would be good for me, she signed on to the idea with a wide smile. After that, the real work started.’

‘Finding your victims,’ Hunter said, his eyes still on the board in front of him.

‘That’s right. I began browsing through social-media sites, looking for anyone who had, at any time, posted a selfie taken inside a moving vehicle.’ Holden laughed. ‘You’d be surprised by what people post on their pages, Detective, by the pictures they upload. You can find out all sorts of personal information on them, on their friends, on their families, you name it. You can find out about their likes, dislikes, their preferences, where they’re going to be on a certain day and at what time, what they know, what they don’t know, what they should know, but don’t.’ Another animated laugh. ‘Social media sites are like a free market of information on people. Information that they, themselves, freely put out there for others to find.’

‘So your real target was the person taking the selfie,’ Hunter said. ‘The people you called, not the people you killed.’

‘Of course,’ Holden admitted. ‘Killing them would’ve been too easy. That wasn’t the point of the exercise.’

An exercise, Hunter thought. Was that how Holden saw his murders?

‘You know, Detective, I really wish I had died in that car crash, but instead, I got trapped. Did you know that?’

Hunter didn’t. It wasn’t mentioned in any of the reports he’d read.

‘I couldn’t free myself from my seat.’ Holden paused again, long and heavy. When he spoke, his voice was full of grief. ‘My wife and my older daughter didn’t die instantly. It took them almost five minutes to go. I had to watch them die right in front of my eyes without being able to do a thing. I was right there, so close, but I couldn’t move. I couldn’t reach them.’

Hunter breathed in another piece of the puzzle. That had been the reason for the video-calls. Holden wanted his targets to watch the ones they cared for suffer. He wanted them to watch them die, just like he had to watch his family die. He wanted them to feel powerless, just like he had felt that night.