With nothing else to learn about Rory’s stay in the hotel, we thank the receptionist and make our way to the door, which slides open upon our approach. With confirmation that Rory stayed here, two thirds of the ANPR dots are accounted for. Now, it’s time to verify the final third.

A quarter of an hour later, we pull up in front of a row of run-down shops and Liam looks slightly anxious about leaving the car in such an area. I grab the picture of Rory from the back seat and walk into the shop on the end of the row.

The newsagents is full to bursting with discounted stock. Brightly coloured card, cut into the shapes of firework explosions, display appealing prices and buy-one-get-one-free offers. Boxes full of multipack, not for individual resale crisps line one wall and a bored-looking man with his hair brushed forward and a mono-brow, who is on his phone and speaking rapidly in a language I do not understand, sits behind a shelf full of assorted chocolate bars.

‘Do you recognise this man?’ I ask, holding the photograph of Rory above the display of food. He doesn’t stop his phone call and barely looks at the picture before waving his hand and shaking his head. We leave the shop without another word, whilst he continues his conversation.

‘The big man needs to work on his customer service,’ Liam remarks, as we make our way into the next shop. The same uncooperative attitude follows us down the row, until we get to a doorway with a metallic shutter pulled over it. The sign above the doorway shows that the premises are used as a massage parlour and through an eye-level slot, presumably used as a letter box, I can see a set of stairs. I ring the bell and a lady’s voice crackles through the intercom system.

‘Not open ‘til five, sorry.’

I press the button at the bottom of the communication device, hopefully allowing whoever is upstairs to hear me. I explain who we are, why we are here and ask her to come to the door. A minute later, a pair of eyes are looking at us through the slot.

I hold the picture of Rory up so that whoever is behind the door has an unhindered view, and the look in her eyes tells me we have found someone who knows Rory.

‘Harry,’ says the woman, in a thick Eastern European accent. Liam and I look at each other.

‘May we come in?’ I ask. The woman nods and makes her way back up the stairs. I am about to ring the bell again, assuming she has misunderstood me, when the shutters begin to rise off the ground. It stops halfway up, forcing Liam and I both to bend down and shimmy underneath it. As we make our way up the stairs, the mechanical noise of the shutter starts again and I turn to watch it clash with the pavement, sealing us in.