They’d become more regular after that, until Kelly had sought the advice of the National Offender Management Service (NOMS) which handled such harassment from prisoners, past and present. The letters were coming from Amy Richmond, a serial killer put away by one of Kelly’s former investigations. She’d been menacingly dubbed ‘The Teacher’ by the press at the time and it still made Kelly shiver. However, they’d yet to figure out how she was getting the letters out of Broadmoor, the high security loony bin which held such dangerous prisoners. Neither Kelly, nor her team, ever judged Amy as insane: she knew what she was doing and why.

Somebody must be mailing the letters on her behalf, but who? Correspondence from Broadmoor was heavily vetted, unless there was a bent guard – always a possibility. The postcode was a local Bagshot one, near the hospital, on the Surrey/Berkshire border.

At that point, around six months ago, something else had struck Kelly. Instead of launching a formal investigation into the correspondence, Kelly toyed with the idea of using them to her advantage. The letters themselves could hold the key to the psyche of the writer, and could be potentially important in the future study of psychopaths. They could also possibly lead them to a copycat killer. It had been done before. Psychopaths like Amy Richmond often studied the work of their heroes: other killers.

HQ had suggested a positive mindfulness course for her and her team in reaction to Kelly’s suggestion. She’d initially turned up her nose. Mindfulness – or the conscious awareness of the energy surrounding all living things – was a thing in workforces now, apparently. But within a police force? When crime was the manifestation of the opposite of such drivel? Kelly was a staunch cynic when it came to sending her officers on courses that concentrated on feeling empathy. Not that she was opposed to relating to human emotions in others – far from it – but, as law enforcers, they dealt with the damaged, the ruined, the damned and the downright sadistic. A bit of tree hugging and meditation wouldn’t cure them.

HQ got their way, and she and her team had endured five sessions so far. They’d taken place at Eden House and a budget had been arranged to provide biscuits, coffee and juice. Kelly had said to Johnny she’d rather put the money towards catching bastards, but she didn’t know how to put that in writing.