The MCRTF office was busy when Anna and Khosa arrived back. Rainsford was at the whiteboard with two other people Anna had not met before. One was a woman. Small, dark hair, dark brown – almost black – eyes with no way of differentiating pupil from iris. Her mouth was wide, and her skin olive-tinged under black jeans and a white blouse. She would not have looked out of place on the streets of Milan or Madrid. The other, a man, was a little overweight, his paunch sagging over his belt, tie loose over an unfashionable, and unseasonal short-sleeved shirt. He had a full face with a small nose and unruly hair that looked as if no amount of combing could control the way it wanted to curl. She put him at around forty. His eyes locked on to Anna’s, appraising and a little knowing. She felt at a slight disadvantage.

Rainsford spoke. ‘OK. Introductions. Inspector Anna Gwynne and DC Ryia Khosa, this is Detective Sergeant Leah Cresci from South Wales Police. Sergeant Cresci’s been involved with the investigation into Kimberley Williams’ suicide and is on their task force looking at other Internet-related deaths.’

She shook Cresci’s warm, dry hand. When she spoke it was a Cardiff accent that emerged. ‘Nice to meet you, ma’am.’

Rainsford turned to the man. ‘DS Phil Dawes is from our own Major Crimes Unit. He’ll be liaising with Sergeant Cresci on this. Given Shaw’s link to the Black Squid and his conviction that what we’ve found next to the railway tracks are Black Squid-related, it seems sensible to expand the remit. If there is a link and if there is still someone out there responsible for goading kids into suicide, this may provide us with a golden opportunity for a new line of investigation. Sergeant Dawes will be joining your squad, Anna. You remain the senior investigating officer.’

Dawes, too, held his hand out. Khosa shook it and then so did Anna. His eyes held hers, small but full of a hunter’s intelligence.

Jamie Carson’s photograph was posted up. Trisha appeared at Anna’s elbow and handed her another black-and-white printed image, this one of a woman of about Anna’s age, hair cut in a boyish pixie style, smiling for the camera. Anna stared at it and turned it over to read a handwritten line.

Alison Bridget Johnson, reported missing 9 August 2001.

She kept the photograph in her hand. ‘OK. Shall we?’ She pointed to Jamie’s image. ‘Jamie Carson was fifteen when he disappeared. He’s been missing since 8 August 2001. I’ve spoken to his family, and Gupta’s just confirmed dental records match. I also found a sketchbook at Carson’s house with images of the black squid, and a likely timeline of instructions. The initial investigation was unaware of its significance. He also left a note with the words “Gone to Ink”.’

The faces staring back at her reflected her own disgust. ‘Jamie’s brother told us he used an Internet café, which, according to Trisha’s enquiries, no longer exists. We need to see if there is any record of who owned and ran it and if there’s an IP address and ISP record, though we have no idea of the timings of Jamie’s visits there so it’s a shot in the dark.’

Holder nodded and wrote on a pad.

Anna pointed to Abbie’s image. ‘Abbie Shaw. Known victim. Unfortunately, most of what we know about her involvement with the Black Squid is in her father’s head.’

‘Can I help with that, ma’am?’ Dawes asked.

Anna shook her head. ‘He only speaks to me.’

Dawes frowned.

‘Long story,’ Anna said, ‘and believe me I wish it wasn’t true. But it is.’ She turned back and pinned up the image Trisha had just given her. ‘The second corpse. No confirmation of identity yet, but this is a strong candidate. Alison Johnson, missing since 9 August 2001 but last seen on 8 August 2001, the same day that Jamie Carson became a misper. Alison worked as a nurse at Ryegrove’s secure unit. Trisha is pulling her misper files. We can’t be sure this is her, but for now it’s the best lead we have. We’ll need to interview friends and family and colleagues at Ryegrove. Confirmation, as with Jamie Carson, will come from familial DNA and dental records.’ She turned to Holder. ‘Justin, check if copies of the dental records are on file already. Given that she was reported missing, the investigating team would probably have had copies made in anticipation. If so, get them over to Brown and Gupta right away.’

‘What else makes you think it’s her?’ Dawes asked.

‘Remains are the right age, the engagement ring fits the profile, and there’s a magnetic strip key card like the ones that are used at Ryegrove. Forensics have both the ring and the key card as we speak.’

Rainsford nodded. A faint smile played over his lips. Anna took it as a sign he was pleased. ‘Thanks, Anna. DS Cresci, could you fill us in on your side?’

Cresci stood on the other side of the board and addressed the team. She pressed a remote, and a TV screen in the corner lit up. She held herself upright, addressing them in an efficient, capable manner. ‘I think you all know the background.’ A photo of a girl with dark hair and acne-ravaged skin appeared on-screen. Her hair looked wild and windswept, and her face bore black marks and streaks. It looked like she’d been the victim of some insane face-painter, but it was the expression of abject misery that drew everyone’s gaze. That would stay with the team long after Cresci had gone. ‘Kimberley Williams threw herself off a cliff in Southerndown after painting her face with an image of a black squid. Before she did, she took a photograph of herself and posted it on her Instagram account.’

‘Was that image made public?’

‘It was. We had her phone looked at. She was in communication through WhatsApp with a user known as Humboldt. For those of you who aren’t aware, there is a type of sea creature known as a Humboldt squid. There are transcripts of communications between Kimberley and Humboldt. They run over several weeks and it’s clear she was being groomed for some sort of final act.’

‘Can we see those?’

She held up a cardboard file.

‘So, you know who she was talking to?’ Holder asked.

Cresci shook her head. It was a resigned gesture that told Anna she’d known the question was coming. ‘That’s where it becomes difficult. Our tech people have tried to trace Humboldt but he covered his tracks well. Most of us know WhatsApp, right? It’s popular because it encrypts messages. Anyone can sign up, but the sign-up process uses a phone number for verification. These days you can sign up for a virtual phone number with a throwaway email address. There are apps that do this for you. Humboldt used a WhatsApp account that never revealed his ID.’

‘Is that even legal?’ Holder frowned.

‘It is. But it’s a huge security issue. Bottom line is that the WhatsApp account Humboldt used was completely untraceable.’

‘So why did Kimberley get involved with Humboldt?’ Khosa asked.

‘She was unhappy. She’d broken up with a long-term boyfriend. Struggled in college. In fact, she was being medicated for depression. But she claimed they made her put on weight and so she stopped. Her Internet search history shows she spent a lot of time online looking at suicide websites. After she visited one site in particular, she stopped looking and that was when the WhatsApp relationship with Humboldt began. We’ve interviewed family and friends. They paint a picture of a bright girl striving and failing to compete academically and socially. There were issues around her skin condition, too, and she was undergoing treatment for that.’

Shades of Abbie Shaw there, Anna thought. From photos of Shaw’s daughter, Anna knew she also struggled with her skin. It had sapped her confidence. One of many reasons she’d probably had a tough time at school and sought solace in online chat rooms. Just as Kimberley had done.

Rainsford spoke to Cresci. ‘Thanks, Sergeant. The question is, does it link in with our supposed Black Squid cases? And if so, how? There’s a significant time gap.’

Anna nodded. ‘But this isn’t the only case of late, am I right?’

Cresci shrugged. ‘Sporadic reports from Holland and France. Three confirmed cases in the UK over the last two years. We’ve hit a roadblock with Kimberley and the Black Squid isn’t the only game of this type. But with the coroner referring the case to the Association of Police and Crime Commissioners, it’s made everyone sit up. One of the reasons I’m here, ma’am, is that when I typed Black Squid into HOLMES, Hector Shaw’s name lit up.’

‘Why do they keep calling it a game?’ Khosa said, her distaste obvious.

Cresci said, ‘Challenge would be better. Let me show you.’

The rest of the team sat around Khosa’s table, which was the tidiest in the office. Cresci opened her file and laid out ten sheets of paper, each one covered in typed exchanges, some highlighted. ‘Underlining indicates Humboldt.’

The first exchanges were brief and with warnings.

‘For God’s sake,’ Dawes said. ‘That’s dated 15 July last year.’

Cresci nodded. ‘Kimberley must have thought about it for a few days. She sent back the image a week later. There was a copy on her phone.’ She turned back to the screen and pressed the remote again until she found the image she wanted. Kimberley Williams in her bathroom, a crude, bloody shape on her forearm, her face solemn and unhappy.

Cresci went back to the transcript. ‘On 23 July, Humboldt accepts Kimberley’s commitment.’

‘This is sick,’ Holder said.

‘The exchanges continue. Humboldt manages to get inside her head,’ Cresci said. ‘He accesses her social media, knows who she’s been talking to, knows what she’s been saying. He’s friendly to start with, then cajoling, then coercing. It’s all designed to isolate and degrade and disorientate through sleep-deprivation and self-loathing. Until the last day. By this time the suicide prep is more or less complete.’

Anna’s eyes had drifted to the top of the second page. Another entry.

‘The Exorcist,’ Dawes said. ‘With the rotating head and green vomit? Put me off carrots and peas for a month when I first saw it.’

But Anna was on her feet and on the way to her office. She came back with the sketchbook Tom Carson had given her, open at the page that said, ‘Day 11’ and ‘4AM. Walk alone, count to thirty. Watch XRCST.’

‘Oh my God,’ Khosa said. ‘It’s the same. Or virtually the same.’

‘Maybe this stuff is common knowledge,’ Holder said.

‘A copycat?’ Cresci suggested.

‘Or the Black Squid has been asleep for all these years and has just woken up again,’ Anna said.

‘Long time to be asleep,’ Dawes said. ‘Unless it’s been locked away somewhere.’

Anna tilted her head and nodded. She liked the way Dawes thought.

Cresci said, ‘Whatever the reason, I can’t help wondering how many more Kimberleys it has dangling on the end of its sick phone messages, playing its disgusting game.’

They spent an hour poring over more of the exchanges between Kimberley and Humboldt, asking questions, Cresci answering as best she could. The messages counted down to the last day, with clear instructions for how Kimberley was to proceed with her own death. It made for difficult reading.

Two coffees later, when they’d finished or were unable to stomach any more, Rainsford turned to Cresci. ‘Thanks, Sergeant, you’ve been really helpful. As you can see, we’re right at the beginning of all this on our end. Any suggestions?’

Cresci shrugged. ‘Shaw seems to be the link here. It would probably make sense for me to interview him.’

Everyone turned to Anna. She repeated what she’d said to Dawes. ‘You’re welcome to try. Up to now he has refused to talk to anyone but me.’

‘So I’ve heard,’ Cresci said. There was no subtext. Just irritated regret. ‘I assume that once both bodies are formally identified, you’ll be interviewing him again, then?’

‘Possibly,’ Anna said, not wanting to agree to anything at this stage.

Cresci looked at her oddly but said nothing.

Rainsford nodded his approval. ‘OK, we’ll let Sergeant Cresci get back to Cardiff. Phil will be in touch with anything we find and, obviously, if anything new comes up in the Williams investigation, you’ll let us know.’

Cresci did another round of shaking hands and Rainsford walked her out.

Once she’d gone, Anna got down to business. ‘So, actions?’

‘Chase up Alison Johnson’s misper file and dig out what we can on Carson. Speak to remaining relatives and friends. Gee up the forensics, dental records, etc.,’ Dawes said. ‘I can rope in another DC from MCU for legwork if needed. And we’ve got two extra for the HOLMES team.’

Anna nodded. She felt suddenly fired up. They’d never had this much help before and having a couple of extra people inputting data into HOLMES would be a big boost for Trisha. ‘Great. Justin, you work with Sergeant Dawes on Johnson. Trisha, see if you can get Jocelyn Mitchell. Tell her I’d like to set up a meeting with her tomorrow at Ryegrove. Ryia, I’ll want you with me on that but before we do, we’d better go back to Mangotsfield and tell the Carsons the dental records confirm it’s Jamie that we found. I’d rather do that in person.’

Everyone got up at once. There was a lot to do.

Though Cresci had gone, Anna couldn’t help but dwell on what she’d told them about Kimberley. This was the destruction of a human being from a distance. A sick and twisted game with death as the prize.