The MCRTF team had a home on the second floor of Avon and Somerset Police HQ at Portishead. It was an open-plan room with four desks and a cubbyhole that Anna called her office. Every desk held a computer screen and file trays loaded with paper in various guises, and every wall had shelves stacked with labelled box files. Two of the desks were occupied. At the nearest one to Anna sat a young woman whose sleek short black hair and dark eyes had been well hidden by her outdoor gear at the site the day before. Khosa’s competence as a detective constable was only exceeded by the size of her extended family. She had an aunt or uncle in almost every Midland town, and Anna wondered if Khosa’s move to Bristol had in part been driven by her need for a little freedom. A change of hairstyle and some new clothes to go with a slimmer profile had not gone unnoticed over the past weeks. But most telling of all was how Khosa had given up ribbing Holder for his romantic escapades. Anna suspected Khosa had a partner and that glass houses and stones did not go together well.

Next to her sat Trisha Spedding, the team’s civilian analyst. Early forties, she was older than Anna by over a decade and looked after herself and her teenage sons. Trisha was a sounding board for all things practical and a skilled organiser. Something Anna found invaluable. Talking to Trisha with his usual restrained congeniality, Rainsford looked dapper in a grey suit, white shirt and a tie with some tiny repeating pattern, which, Anna suspected, only meant something to someone with military connections.

It was a little after 9.15 a.m. and Holder texted her to say he was on his way down from the lab. Pasted images of the crime scene with indicators for where the bodies had been found were up on the board. She contemplated these now, marking the fact there was a lot of blank space between. She hoped Forensics would have something she could add. On cue, the door opened, and Holder strode in, looking triumphant and waving some photocopied sheets of paper.

‘Got him, ma’am. Photo ID in the shape of a CitizenCard.’ Holder began sticking A4-sized photographs to the board.

‘What’s a CitizenCard?’ Khosa asked.

Rainsford answered, moving closer to look at the images. ‘Photo IDs that began in the late nineties, I think. In response to the No ID, No Sale campaign that tried to help retailers with age-restricted goods. They carried the Proof of Age Standards Scheme hologram.’

Khosa stood to join the superintendent and Anna. A brown stain covered one half of the image, blurring the face but still bearing the print that clearly read ‘Under 16’.’

‘In case you can’t read it,’ Holder explained, ‘this belongs to a male, Jamie Carson, date of birth, 15 June 1986. The card was issued on 15 June 2000. Carson went missing on 8 August 2001.’

‘Anything else in the wallet?’

Holder’s mouth turned down. ‘Not much. Some money. Couple of notes and a few coins.’

Anna turned to face the team. ‘So we have a name we can run, assuming no one has deliberately planted someone else’s wallet to confuse us. If Shaw’s timeline is correct, and the remains are those to whom the wallet belongs, Jamie’s body has been in the ground for almost seventeen years. That’s a long time for his family to wonder what’s happened to him.’

‘Do we think that this is related to the death of Shaw’s daughter?’ Holder asked. ‘Something to do with the Black Squid?’

A good question. One Anna knew she’d be asked. One she’d prepared for. ‘We don’t know anything about him yet, but he’s the right age to be a Black Squid victim.’ She ducked out of the room and into her office. When she emerged, she clutched a one-inch-thick file. ‘I’ve been doing some homework just in case.’

Rainsford said nothing, but his eyebrows shifted up an inch.

On the board, Anna put up a photograph of a young girl. Big eyes heavily made-up with pink and grey eyeshadow and way too much eyeliner in an attempt to make her look older than the thirteen she’d been when the image was taken. Black hair with a pink fringe hung low over her brow. On a sweatshirt beneath were the words ‘My Chemical Romance’.

‘Abbie Shaw,’ Anna said. ‘Taken two months before she threw herself under a train just before Christmas in 2001. She was thirteen. It was her death that triggered her father’s murderous, misguided vendetta.’

Next to Abbie’s image, Anna posted a stylised black block-drawing of a squid. An arrow-shaped body above, two large eyes on the sides and, protruding from the front end at the bottom, eight arms and two tentacles curling menacingly. ‘There wasn’t much left of Abbie after she stepped out into the path of the London to Manchester express, but a crude version of this image was painted in black felt tip on her cheek.’

From her file, Anna took a CSI image with Sussex Police’s logo stamped upon it. ‘This is what we found at the end of last summer when Shaw took us to Sussex.’ She pinned up a second image. A boy in school uniform, buck-toothed, smiling at the camera. ‘Dental records and DNA confirmed this to be Daniel Litton, aged fourteen at the time he went missing.’

The silence in the room was almost palpable as Anna kept going, adding another sheet to the board. This one much more recent. Post-mortem images taken from the site of Kimberley Williams’ suicide. She was lying face down on the rocks. The part of her head that was visible had been roughly edited, masking out parts. Her eyes – what were left of them after the deceleration of hitting the stone ‘beach’ floor smashed them into unrecognisable mush – were taped over, as was what was left of her lower jaw. But on the skin of her cheek and on her nose a dark smudge was visible. ‘I got these this morning from South Wales. This is Kimberley Williams, who died five months ago. She threw herself off a cliff.’ Anna turned away from the board. ‘Three of these are definitely linked. Abbie, Daniel and now Kimberley all left notes for their families.’ Anna reached for the file once again. She did it quickly, so no one would notice how her hand was trembling.

Anger did that to her sometimes.

She removed one other image. One she’d manipulated on the computer that morning to show the three ‘notes’, each consisting of a crude facsimile of the black stylised image of the squid she’d already put up. One had a kiss in the shape of a cross beneath. One had ‘Inky blackness, Mum. It’s the only way. Soz’ written on a Post-it note. The other showed nothing but the image of a squid.

‘Jesus,’ Holder said.

‘If you haven’t already, you’ll need to read up about suicide games. The Black Squid isn’t the only one. They’re much more prevalent in Eastern Europe – 130 deaths, supposedly. Some in the USA. But essentially, they are the same. The classic one was the Blue Whale challenge. Up to fifty tasks designed to tire out the victim by making them wake up too early, watch horror films, self-harm, alienate themselves from support. All verifiable by photographic evidence. It sounds incredible, but these are already vulnerable individuals. There are some who think it’s still a hoax that has perpetrated copycat acts. Kids can be very gullible.’

‘But is there any evidence they didn’t actually commit suicide?’ Khosa asked.

‘No,’ Rainsford answered, drawing everyone’s focus. ‘But as it stands it remains against the law to aid, abet, counsel or procure the suicide of another. That carries a fourteen-year sentence.’

‘I thought the CPS weren’t that keen,’ Khosa said.

‘No one in their right mind in the crown prosecution service wants to stand in court and prosecute someone who’s helped a terminally ill relative on to a plane to Dignitas,’ Anna said. ‘Public opinion in those cases is torn. But this is different. This is someone deliberately manipulating vulnerable kids into doing something because they think it’s a game and ensuring they follow through with it. It’s wrong, cowardly and very prosecutable.’

‘We need to find if there’s anything else linking these cases together,’ Rainsford said. ‘With Kimberley Williams’ death it looks like this game may have resurfaced, but we need to be sure.’ He turned away from the images.

It sounded to Anna as if Rainsford needed convincing. Shame they couldn’t wheel Shaw in. He didn’t need convincing. One look into his murderous eyes would tell Rainsford that.

‘I’ve spoken to the chief superintendent and the assistant chief constable. Given DI Gwynne’s links to Shaw and his extensive knowledge of this case, as well as his direct involvement because of his daughter, they want this squad to investigate Black Squid-related cases, in addition to and alongside the bodies found by Shaw.’ Rainsford turned to Anna. ‘Can I have a word?’

They went out into the corridor, away from prying ears. Rainsford dropped his voice and folded his arms. Never a good sign in Anna’s book.

‘I realise that this isn’t strictly your usual remit, but we’re facing a new round of budget reviews. With so many new cases, cold case squads are easy targets often seen as an expensive luxury.’

‘But we’ve been successful, sir. Haven’t we?’

‘Spectacularly so. However, it’ll do no harm if we can demonstrate a wider benefit. The Williams case has brought cybersuicide into the national awareness and I think I can rope in some help as a result. If this case can shed some light on what’s happening elsewhere, the accountants will have a hard time cutting off our funding.’

Anna frowned.

Rainsford shrugged. ‘It’s a constant battle. I’ll be the supervising officer, mainly for administrative purposes. I’ll get someone over from South Wales Police to brief us on the Kimberley Williams case, too. It’s better that I do the liaising. It’ll free you up to do the ground work.’

Anna went back into the office to join the team, nursing a dull disquiet.

‘What about the second body, ma’am?’ Khosa asked.

‘We’ll know something later this afternoon, hopefully. We already know about Abbie and Daniel. I suggest we put our efforts into finding out about Jamie.’

Trisha, who’d been busy at her computer, spoke up. ‘I’ve run the address found in the wallet. It’s in Mangotsfield and is still registered to the Carsons. It doesn’t look like they’ve moved.’

Anna nodded. ‘Then that’s where we should begin. My lucky day to be the one knocking on some family’s door with the news they’ve been dreading for almost twenty years. Anybody fancy coming with me?’

Khosa and Holder looked at one another.

Anna fetched her coat from her office and slid it on before heading for the door. She paused. ‘Toss a coin, you two. I’ll be in the car. Whoever doesn’t come rings the pathologist. I want to know when those bones are in the lab.’