Now, sitting at the dinner table, she idly flicked though it while her mother took their dirty dinner plates out into the kitchen and went to get dessert.

Her father tilted his head and fixed Bailey with a serious look. She felt a pre-emptive surge of unease. She recognised that expression only too well.

‘Bailey, I want to talk to you about Mister Snigiss,’ he said, arching one eyebrow gravely.

Bailey rolled her eyes. ‘Not again,’ she muttered.

At the time that Jennifer had gone missing, she, like many children her age, had possessed an invisible friend. The name of this invisible friend had been Mister Snigiss. Mister Snigiss had been present throughout many of their childhood games, leading both sisters on an array of imaginary adventures. Bailey remembered how hard she’d always strained to see Mister Snigiss, but only Jennifer had been able to see him, and Bailey had just taken it on faith from her older sister that Mister Snigiss existed.

In the wake of Jennifer’s disappearance, Bailey’s father had seized upon every aspect of her childhood in an effort to try and work out what had happened to her and Mister Snigiss was no exception.

‘I want you to help me find Mister Snigiss,’ he said, without an ounce of irony.

Bailey sighed. ‘Mister Snigiss was nothing more than a figment of Jennifer’s imagination, Dad.’

Her father shook his head. ‘Mister Snigiss was real.’ His eyes bore that all-too-familiar glaze of conviction and Bailey knew he was deaf to anything other than his own dogmatic beliefs.

‘As I recall,’ she said, ‘Mister Snigiss wore a funny hat and had a pet cobra called Sid. Kids make up all kinds of stupid stuff.’

Her father was shaking his head vehemently. He was building up to one of his rants.

‘No! The more I think about it, the more I’m convinced that Mister Snigiss was a real person. An adult. A man who secretly wormed his way into Jennifer’s life. He was grooming her. That’s what he was doing. He told her not to tell anyone about him, told her to make out like he was her invisible friend so we wouldn’t get suspicious. If only I’d paid more attention to her! If I’d known he was real, I could have saved her from him. He was the one who took her. It was Mister Snigiss who abducted her.’

‘Dad, you’re beating yourself up over something that doesn’t exist and never existed.’

But her father wasn’t listening. He was in full flow now.

‘That pet snake of his was probably just a way to lure her to meet him. You remember how much Jennifer wanted a pet snake and we never let her have one. Well, Mister Snigiss told her exactly what she wanted to hear.’

Bailey was starting to run out of patience. It wasn’t that she was uncaring. It was more that because, as a police officer, she’d encountered enough similar cases to know that there was little point in her father holding out hope in this way. After twenty-four years it was time for him to face up to the fact that Jennifer was gone for good, one way or another.