Mangotsfield lay to the north-east of Bristol, on the Gloucestershire border. It had a medieval church and a manor house and an honourable mention in the Domesday Book. The village, originally housing miners and farmworkers, grew to absorb the surrounding hamlets. Despite the inevitable urban expansion, it had not quite shaken off its rural background. The Carsons lived in a house covered in cream-painted stucco on Charnhill Road. Two cars sat on a drive made of compressed concrete coloured to look like brick. A plastic hammer and chisel from a child’s toy toolset lay abandoned in the porch. Khosa stood next to Anna as she rang the bell. She hadn’t commented in the car whether the toss was lost or won. They both knew this was part of the job.

A shape appeared, blurry through the random pattern of the obscure glass pane in the porch door. The man who eventually opened it looked older than the sixty Anna knew him to be. Jamie’s father, John Carson, had retired from the docks with back problems. From the look of his ample belly and the veins around his nose, it hadn’t stopped him visiting the pub.

‘Help you?’

Anna showed him her warrant card. ‘Detective Inspector Gwynne, Mr Carson. This is Detective Constable Khosa. We’re here about Jamie.’

John frowned and shook his head. ‘Jamie don’t live here anymore.’

Anna nodded. ‘We know, Mr Carson. We’re here with news about his disappearance.’

John’s eyes were blue islands in a florid face. They narrowed now. It was difficult to judge his expression, but his lower jaw suddenly began to tremble. ‘Come in,’ he said, turning away and began to shout, ‘Gill, Gill! There’s police here. It’s about Jamie.’

Anna followed with Khosa behind. John stood in the corridor, blocking off the rest of the house and ushering them into a front room full of lived-in furniture. A couple of sofas in brown leather, the cushions on the seats hollowed out from years of sitting. A wall-mounted TV sat above a cabinet full of DVDs. The carpet looked shabby with a couple of suspicious stains. In two corners sat piles of toys: cars, action figures, bits of Lego. More evidence of children.

From somewhere at the rear of the house came conversation, muted through the walls, the rise and fall of surprise and anxiety in equal measure. The Carsons appeared in the doorway together. Gill Carson was not tall, ample around the waist, and her straw-coloured blonde hair framed a round face without make-up. She wore jeans and a rugby shirt with the sleeves rolled up. Behind her stood a taller, thinner man.

‘Mrs Carson,’ Anna said. ‘Sorry to intrude.’ She looked up at the taller man and judged him at early thirties, his hair already starting to thin, his complexion pale but his arms, in the T-shirt he wore, defined from work or sport. ‘And you must be Tom.’

Tom Carson nodded. Below him, a head appeared, dark-haired, wide-eyed, pulling at Gill’s leg.

‘Hello,’ Khosa said.

The face pulled back, cowed.

‘My grandson, Orlando.’ Gill turned to her surviving son. ‘Tom, put a video on for him in the playroom.’ She turned to the little boy. ‘Want to watch Paw Patrol?’

Orlando let out a delighted, ‘Yeaaahhh,’ and disappeared with his father.

‘What’s this about?’ Gill asked. Colour had rushed to her cheeks and Anna knew this needed to be done swiftly.

Tom reappeared, and the Carsons once again crowded into the room. Gill and John on one settee, Tom in an armchair, which left the other settee for Anna and Khosa. But Anna chose to stand with her back to the window.

‘There is no easy way to say this and so I’ll get right to it. We’ve found some remains near the river at Leigh Woods. At present we’ve been unable to confirm identification, but we found Jamie’s ID card inside a wallet with the victim.’ She nodded at Khosa, who placed two photographs on the coffee table. One of the wallet after Forensics had frozen it and vacuum-dried it, and one of the CitizenCard. The Carsons leaned forward. Gill was the first to turn away, a sob catching in her voice, her hand unable to suppress it as it emerged, the first in a series ratcheting from her throat. Her husband put his arm around her, big hands squeezing her shoulder ineffectually.

‘You said remains?’ John asked, his blue eyes already angry.

‘Whoever it is that we’ve found has been buried for a long time.’

‘Do you want me… Do I need to see the body?’

Anna shook her head. ‘Identification will need to be by dental records, maybe DNA. After this length of time there’s nothing for you to see.’

John stared at Anna, but she knew he wasn’t seeing her. The trembling in his lower jaw had become much more obvious. It was Tom who seemed the most able to take things in.

‘These are Jamie’s,’ he said after a while. ‘The wallet and the card. They are his.’

Khosa took her cue. She stood and said, ‘Mr Carson, a cup of tea is usually good in these situations. Can you show me?’

John looked at her but didn’t see her, then he blinked and stood up. ‘The kitchen. It’s at the back.’

Khosa helped Gill up. ‘Come on.’

She didn’t argue. Grief had rendered her compliant.

Anna waited until they’d gone and then said, ‘I’m sorry to bring this to your door.’

Tom shrugged. ‘It’s not as if we weren’t expecting it. But Mum… she’s never quite accepted… It’s hard.’

Anna nodded. ‘If the remains are Jamie’s, then I need to try and find out what happened.’

Tom nodded.

‘You’re living here?’ Anna asked.

‘Me and Laura, that’s my partner. We’re trying to save up for a place. You know how it is.’

‘When Jamie went missing, there was an investigation, I know.’

Tom nodded. ‘They came round, went through his stuff. But they thought he’d run away.’

‘Did he have a reason to?’

Tom shook his head. ‘Not from here. But Jamie had a hard time at school.’

‘How so?’

‘Wasn’t into sport. Liked his music, but not the stuff I was into. Bit of a loner, to be honest.’

Anna nodded. ‘Did he speak to you about things?’

‘I was his brother. We didn’t speak about anything serious. I was caught up in my own stuff.’

‘Did he spend much time on the Internet?’

Tom shrugged. ‘Not here. We had dial-up access and one computer. Dad was always on about the phone bill. Jamie used to go to an Internet café over in Fishponds.’

‘Mobile phone?’

‘Yeah. An old Nokia. We both had one. Pay as you go.’

‘Was that ever found?’

Tom shook his head.

Anna put the block image of the black squid on the table. ‘Does this mean anything to you?’

Tom stared, leaning in closer. He looked up at Anna, perplexed. ‘Yeah, I mean I’ve seen it before.’ He got up abruptly.

‘Where are you going?’

‘I won’t be a minute.’

She heard his feet taking the stairs two at a time. He returned within two minutes carrying a file folder. ‘This was Jamie’s.’ Tom opened the folder. Inside was a jumble of papers, postcard-sized photos of bands, cuttings, the odd ticket stub and a sketchbook. Tom took everything out and flicked through the pages. Doodles and sketches mostly until he got to a page towards the end. He stared at it momentarily before turning it around to show Anna. On it, sketched in dark ink, was an unmistakable image of a dark shape with eight arms and two tentacles.

Anna took the book. Jamie had also written ‘Day 1’ and ‘silent running’.

Anna turned the page over. The same image, but this time with ‘Day 11’ and ‘4AM. Walk alone, count to thirty. Watch XRCST.’

‘Did you show this to the police?’

‘Yeah. They gave it back to us after a week. Said it didn’t really help much.’

‘Did he say anything to you before he went? Leave anything, a note?’

‘Not really, only this.’

‘This?’

Tom nodded and reached into the pile again to pull out one single sheet of A4 paper with the words: ‘Gone to Ink.’

‘The police thought it meant he’d gone to get a tattoo.’

Anna stared, her pulse ticking a little louder and quicker in her throat. The police would have sought to interpret these words, and a rebellious teen announcing he was off to get a tattoo would have fitted.

She turned back to the book and began flicking through the pages. She counted twenty squid images. On the last one, ‘Day 20’, Jamie had written ‘terminal’.

‘Can I take this?’ she asked Tom.

‘Yeah. What does it mean?’

‘I can’t be sure. Not yet.’ She delivered the words automatically, wanting to be as truthful as she could. The original investigators had suggested naturally enough that ink could mean a tattoo. But it had a very different meaning in relation to Shaw and his daughter’s death.

And coincidence, in Anna’s book, was a very dirty word.

Her pulse ticked up another notch.

Tom nodded, happy to accept her lack of commitment. ‘You think these remains are definitely Jamie’s?’

‘We can’t say for definite. Not yet. But I’d say it’s highly likely.’

Tom nodded and sighed. Even though he’d admitted to having expected the inevitable, now that it was here, it was an unwelcome guest. ‘He was different, you know?’

Anna nodded. She did know. All too well.

‘He wasn’t like me. But he was my brother.’

Anna half turned away. ‘Someone from Forensics will be along to take some swabs for DNA. It’s belt and braces these days. They can do familial tests and match it with what’s left of the remains. That way we’ll be absolutely certain. But I think the chances are slim that this is someone else.’

Tom nodded. ‘We had no idea he was doing this. That he felt like this.’ He glanced down at the drawings.

Anna didn’t say anything. This was murder by stealth and guile. But still murder.