Gillard wasn’t the only one trying to find Ozzy Blanchard. Rain was lashing down driven by a chilly north-westerly wind as Ray Slater’s Nissan coasted into Wantage Leisure Park at six on Monday evening. Carl Hoskins’ last gift to him was to identify Crystal’s camper van from the DVLA records. A white 2006 VW. Not the classic type, more like a boxy people-carrier with a concertina roof and just enough space for a good argument. And now he seemed to be scouring the world looking for it.

Since Hoskins had got cold feet, Slater had had to do more legwork himself. No ANPR to make life easier, no cell phone triangulation. Back to the old-fashioned stuff. At first he had telephoned likely caravan parks, but discovered that they were frantically busy, understaffed and slow to answer the phone. When he did speak to anyone, they were reluctant to share any customer details. Each site was supposed to note vehicle registration numbers, but payment for casual guests was usually taken on arrival, and the rental forms they filled out themselves were often illegible. In the frenzy of reopening, Crystal Willow wouldn’t have found it hard to cover her tracks, or to conceal her boyfriend. Slater had never bought the idea that Blanchard was dead. If he was, why would the Tickett family be racing all over the place? He’d watched their cars come and go, and sometimes followed them. He had inside information that showed they still had a score to settle with the missing water engineer. That much he was sure of.

Years of experience had demonstrated to Slater that to get the attention of potential witnesses you need photos. Ozzy’s picture was taken from his LinkedIn account, while Crystal’s was from her massage website. He hadn’t so far met anybody in a campsite who recognised either of them, but quite a few had asked if there was a reward. That was when he would mention £50 in cash for a confirmed sighting, as long as it included an emailed picture. He’d handed out sheaves of business cards with his email address. He was open about being a private detective, and when asked what the couple had done said simply: ‘Indecent pictures of kids.’ If the cash wasn’t enough to justify a holidaymaker touring his campsite to find them, this heinous (and false) accusation would often be. He knew that the word would get around very fast. Almost no one that he talked to amongst the holidaymakers questioned his right to be chasing such people rather than reporting them to the police.