She gave him a look, not of disappointment, but something else. As if they had just had an argument which he had lost and she had trumped it with: I told you so.

‘What’s up, Mel? Has something else happened?’

‘I found some more drugs, in her room.’

‘What kind?’ He started to move towards the stairs, to start examining this domestic crime scene.

She held him back. ‘I don’t know exactly, I flushed them all down the loo.’

‘What? Why did you do that, Mel? How are we ever going to—’

She seemed distracted, glancing over his shoulder towards the door into the house.

‘Is she here?’ he asked, turning to look too.

‘No, John. She’s not. She is never here at a Thursday lunchtime, she’s got that part-time waitressing job, remember?’ Mel said, looking back at her husband. ‘I’ve not seen her since Monday, but she texted me a few times.’

Now released, he went upstairs to the spare room which he used as his home office. In doing so he passed Vanessa’s room, ‘Keep Out’ in large stick-on letters on the door. He took a deep breath, turned the handle and peered inside. Many crime scenes were tidier. The bed, a double mattress on the carpet, was unmade and there were clothes all over the floor. The place reeked of sex. Clearly, despite Mel’s certainties, Vanessa had sneaked back with her boyfriend. Perry went inside, and opened the window. As he looked out, he saw that the black Range Rover had gone. He wished now he had made a note of the registration number.

‘Mel, I think she’s been back recently,’ he called down.

‘Really?’ she shouted back up to him.

‘For God’s sake, didn’t you notice the whiff when you were up here? It’s like a bloody bordello.’ He pulled back the duvet on her bed. A used condom, scrunched up tissues and a tell-tale patch on the dark blue sheet, not yet dry. Christ almighty! The girl is seventeen.

‘Mel, it’s disgusting.’

‘I’ve not been up there today. I can’t face it every day.’

‘I can see why,’ he replied. Then, looking at his daughter’s pillow, he saw something on it. Something that changed everything.

Later that afternoon, Gillard and Perry sat in one of the meeting rooms going through everything that was known about Jane Morris. They started with the newspaper coverage, finishing with one piece on the one-year anniversary of her disappearance.

It was a chilly October evening when fifteen-year-old Jane Morris left the sweetshop where her friend Sarah worked, to walk the half mile back to her home in Balham, South London. The shy, mousy-haired schoolgirl was well known to many of the stallholders in the Hildreth Street market that adjoined Balham High Road. Her uncle Harold was one of them and described how he saw the girl talking to a young dreadlocked man with a Bob Marley T-shirt. It was the last time she was seen. Detectives initially arrested and charged a local man, Dudley Jives, who matched the description, but he was acquitted when it became clear that there was no forensic evidence against him, and his initial confession had been provided under duress. Since then police have had little luck tracing the man, despite extensive door-to-door enquiries in the area. It is now a year since Jane disappeared, and her parents Frank and Eileen fear that she may never be found.