The trace of pollen recovered from the edges of the dress. This corroborates the results from the footwear – showing direct contact of the fabric with brushings of ash and birch pollen into the weave of the fabric, both of which peak in pollen numbers from April to May . . . I’d say that’s been the last place she visited alive in the late spring.

If you want to discuss further, just give me a call.

Jen XX

Chrissy had been reading alongside her. ‘So Mary did return from chapel?’

‘And she went to the den or the woods,’ Rhona said, ‘still wearing her confirmation outfit. Doesn’t that strike you as odd? If the dress was borrowed or even if it wasn’t, going to a den in the woods would likely get it dirty.’

‘She was going to meet someone?’ Chrissy tried. ‘Maybe her pal?’

‘Her pal’s house was across the road from the school. Karen was probably waiting for her there. Why go to the woods?’

The most probable answer was that she was going to meet someone. But if not Karen, then who?

‘Whoever it was, they were either the last person to see Mary alive . . .’ Chrissy said.

‘Or the person who abducted and killed her,’ Rhona finished for her.

They were convinced by the evidence that Mary had been naked when she’d died. So her abductor had managed to subdue her as far as his vehicle. Whatever happened then probably sealed Mary’s fate.

‘What if it was a stranger?’ Chrissy said. ‘Paedophiles like Robert Black stalked their victims all over the UK.’

Rhona had considered that too. But how would a complete stranger know about the confirmation or the fact that Mary was going to the den, when she should have been at the school with the other newly confirmed kids? This felt closer to home. She told Chrissy so.

As for the blue jumper she’d found in Karen’s attic, if it was part of Mary’s missing outfit, how had Karen come by it?

‘And so we come round to Karen again,’ Chrissy said.

‘We have Karen’s toothbrush from the cottage, so we’ll soon have her DNA,’ Rhona said. ‘At least then we can establish if she was the other wearer of the dress.’

‘You’ll have to watch your time,’ Chrissy reminded her. ‘The autopsy’s at two o’clock.’

‘I’ll set an alarm,’ Rhona promised.

50

The screen was divided into half a dozen different images, so fuzzy that to McNab’s mind the CCTV footage might not even contain humans, let alone ones he might recognize.

‘These are all from the city centre,’ Ollie told him. ‘One in a corner shop, a cafe, in the queue for Greggs, the rest in various streets. She’s in them all.’

‘Where?’ McNab said, narrowing his eyes as if that would make any difference.

Ollie patiently went through all the images, pointing specifically at the figure he claimed was Karen Marshall.

‘This woman ought to have been a spy. She’s practically invisible,’ Ollie said, sounding impressed. ‘It’s as though she knows no one is aware of her existence, even a security camera. She’s hiding in plain sight.’