Wait. Think.

He’d asked Holmes to read up on the Spaven case, and that meant going through the files. When Great London Road police station had been burnt to the ground, a lot of files had gone up with it, but not the older stuff, because by then the older files had been shipped out to make space. They were stored with all the other ancient cases, all the clanking old skeletons, in a warehouse near Granton Harbour. Rebus had guessed Holmes would sign them out, but maybe not …

It was a ten-minute drive from Fettes to the warehouse. Rebus did it in seven. He allowed himself a grin when he saw Holmes’s car in the car park. Rebus walked over to the main door, pulled it open, and was in a vast, dark, echoing space. Regimented rows of green metal shelves ran the length of the warehouse, filled with heavy-duty cardboard boxes, inside which lay the mouldering history of the Lothian and Borders force – and the City of Edinburgh force until its demise – from the 1950s to the 1970s. Documents were still arriving: tea-chests with labels hanging from them sat waiting to be unpacked, and it looked like a changeover was taking place – lidded plastic boxes replacing heavy-duty board. A small elderly man, very trim, with a black moustache and jam-jar glasses, was marching towards Rebus.

‘Yes, can I help you?’

The man defined ‘clerical’. When he wasn’t looking at the floor, he was staring off somewhere past Rebus’s right ear. He wore a grey nylon overall over a white shirt with frayed collar and green tweed tie. Pens and pencils protruded from his top pocket.

Rebus showed his warrant card. ‘I’m looking for a colleague, DS Holmes, I think he may be looking through some old casenotes.’

The man was studying the warrant card. He walked over to a clipboard and wrote down Rebus’s name and rank, plus date and time of arrival.

‘Is that necessary?’ Rebus asked.

The man looked like he’d never in his life been asked such a thing. ‘Paperwork,’ he snapped, looking around at the warehouse’s contents. ‘It’s all necessary, or I wouldn’t be here.’

And he smiled, the overhead lighting glinting from his lenses. ‘This way.’

He led Rebus down an alleyway of boxes, then took a right turn and finally, after a moment’s hesitation, a left. They came into a clearing, where Brian Holmes sat at what looked like an old school desk, inkwell intact. There was no chair, so he was using an upturned box. His elbows rested on the desk, head in hands. There was a lamp on the desk, bathing the scene in light. The clerk coughed.

‘Someone to see you.’

Holmes turned, stood up when he saw who it was. Rebus turned quickly to the clerk.

‘Thanks for your help.’

‘No trouble. I don’t get many visitors.’

The little man shuffled away, footsteps receding into the distance.

‘Don’t worry,’ Holmes said. ‘I’ve laid a trail of breadcrumbs so we can find our way back.’ He looked around. ‘Isn’t this the creepiest place you’ve ever been?’