‘Like I said, I need to make a few calls. And DS Chalmers needs to ask you some questions about Agnes’s friends.’

Chalmers blinked. ‘I do? . . . Oh, right, yes, that’s right. Questions. Er, shall we? ’

As soon as they’d disappeared into the kitchen, Logan shut the lounge door again, then clambered into the cupboard under the stairs. There was just enough space to kneel at the tall end without banging his head on the sloping ceiling.

He frowned up at it. Now there was something you didn’t see every day. A pentagram covered the plasterboard, scratched out in red ink. It sat within a couple of circles, with squiggles in various bits, and what looked like Latin around the outside.

Why were teenagers such a bunch of freaks?

A pair of wingnuts sat on the inside of the doorframe. Logan peered outside again. The bolt fitted into a metal bracket held in place by the wingnuts. So if you cracked the padlock, opened the door, unscrewed them, put the padlock back on the now unattached bolt mechanism, then climbed inside – you could pull the door shut, do up the wingnuts again, and no one would know you were in there. From the outside it’d look as if the cupboard was still locked.

He shifted the action figures to one side of the shelf and picked his way through the books. Three of them were hollowed out hardbacks, like the one with Harry and Edward getting intimate. One held a notebook, with curly leaves and squiggles inlaid into the red leather cover. It was full of cramped black handwriting, interspersed with sketches of magic circles and other occult thingies. The next held a little woollen dolly, no bigger than the palm of his hand, with button eyes and a lock of brown hair fastened to its chest with a safety pin; a wizened chicken’s foot wrapped in tartan ribbon – like a really cheap kilt pin; a hairbrush; and a test-tube of something dark and viscous.

Book number three was a lot more interesting. Logan tipped the contents out on the mattress. One pack of cherry-scented pipe tobacco. One old-fashioned long-necked pipe. One blister-pack sheet of little orange pills. And one clear plastic Ziploc bag with what looked like catnip in it. He opened the bag and took a sniff: the sweet, sweaty smell of marijuana.

What kind of person smoked weed in a pipe, like an auld mannie?

There was a lot of it too – enough to get a coach-load of students off their faces for a week. Enough to count as possession with intent to supply.

Logan sat back on his haunches. Why would someone run away and leave that much pot behind? Maybe Agnes got into difficulties with her supplier, or another dealer, and needed to get out of town in a hurry?

Assuming she actually managed to leave Aberdeen before they caught up with her. . .