‘I was on my way to warn you, Dr McLeod, that the heavens were about to open.’ DS Strachan gave a nod to the swiftly encroaching rain clouds, which appeared to be circling them. ‘Are you all finished here?’

‘We just need to take these soil bags and our gear to the vehicle, then we’re off,’ Rhona told him.

There was little doubt from the CSM’s expression he was pleased about that, because it might mean he didn’t have to spend another night out on the moors.

As they passed the lochan on their final trip, raindrops were already beginning to puncture its flat brown surface. Jumping into the van just in time, they watched as the sky opened and deposited what it had held back for the past three weeks. Even now, seeing how swiftly the small stream that fed the lochan appeared, they knew how quickly its water level would rise.

‘The peat bank will be submerged again soon,’ Chrissy said as the windscreen wipers tried to throw the rain off as swiftly as it fell. ‘It’s weird. It’s almost as though we were meant to find her. And we were given just enough time to do that.’

Rhona had the same feeling herself. ‘Seamus Heaney wrote a poem . . .’ she began.

‘“Bog Queen”,’ Chrissy said. ‘I studied it for Higher English.

‘I lay waiting

between turf-face and demesne wall,

between heathery levels

and glass-toothed stone.’

The drumming on the roof seemed to grow louder, drowning their thoughts and Chrissy’s quietly spoken words. On a nearby rocky outcrop, two crows who’d watched them load the van now rose cawing into the air.

Rhona and Chrissy waited in silence for the downpour to lessen, before Rhona started up the engine and began to tackle the now-muddy track to the main road.

‘Can we drop the evidence at the lab, then go for a drink?’ Chrissy suggested. ‘I think we deserve one.’

Rhona had it in mind to head back to the flat and go over the photographs and her notes from today.

Chrissy, reading her like a book, said, ‘No way. Remember what they said at Castlebrae? You must leave time for yourself.’

Rhona thought of Skye and the time she’d spent walking in the hills and on the beaches, and how good that had been for her.

‘Okay,’ she relented. ‘I’ll come out tonight and take some time off tomorrow.’

As they crossed the moor, heading back to Glasgow, Rhona’s mobile rang.

‘It’s McNab,’ Chrissy said, reading the screen. ‘Whatever he’s after, it’s not changing our plans,’ she added in a determined fashion, before switching the call to speaker.

‘Rhona?’

‘We’re both here,’ Chrissy informed him. ‘Rhona’s driving.’

‘You’re finished at the locus then?’

‘We’re on our way back to the lab with the soil from beneath the body,’ Rhona said.

‘Anything further I should know?’

Chrissy told him about finding the cigarette butt.

‘That could be useful,’ McNab agreed. ‘Also, we may have a lead on the identity of the victim from a former detective who worked a missing child case in our time frame.’