‘I found it in the files, and printed it out. I thought it was really interesting. Certainly a new perspective.’

‘What is it?’ Wynne said.

‘Forensic psychiatrist’s report. Take a read. I’ve highlighted the interesting part in yellow.’

Wynne scanned down to the highlighted section.

All of the murders have been committed in ‘cold blood’, by which I mean there is no evidence that the killer was in a heightened emotional state. It is probable they were in some way more focused than usual, but there are no signs of frenzied behaviour. Often in serial killer cases there are significant injuries inflicted post-mortem as, with the victim at their mercy, the killer indulges their wilder fantasies. These can include butchery and /or sexual assault. Of course, these things can also occur pre-mortem; what is striking in this case is their absence.

Wynne looked up at DS Alexander. ‘It is striking,’ she said. ‘We should have noticed that these killings are so dispassionate. Almost like assassinations.’

‘There’s more,’ DS Alexander said. ‘Read the note at the bottom.’

Note, added by Det. Tony Munro following conversation with forensic psychiatrist, Sandy Newell.

Dr Newell indicated that she had suspicions the killer might be a woman. She was clear that this was speculation on her part based on no more than an intuition, and hence not in her report. However, the absence of the elements of frenzied and / or sexual assault pre-or post-mortem leads her to question the gender of the killer.

Wynne picked up the mug of tea and took a sip.

‘You know,’ she said. ‘Dr Newell may have a point.’

‘That’s what I thought,’ DS Alexander said.

‘But I’m not sure it helps us. It simply means we have twice as many suspects. And what about the voice? Australian, and male.’

‘Could be a simple mistake,’ DS Alexander said. ‘Or a piece of mis-direction. The killer said a few words in a deep voice and an Australian accent to put us off.’

‘Maybe,’ Wynne said. ‘Although if there is a link to the Perth murders, all they were faking was the deep voice.’

‘So what’s next?’ DS Alexander said.

‘I don’t know. Keep looking. But’ – Wynne paused for more tea – ‘we are making – finally – some progress.’

Wynne looked at the clock – 2 p.m., so 10 p.m. in Perth.

Munro would be awake.

Maybe.

She dialled his mobile phone number. It rang for a while – she was expecting it to go to voicemail – and then he answered.

‘G’day,’ he said. ‘You just caught me. Another ten minutes and I’d have been dead to the world.’

‘Sorry to bother you so late. But I wanted to talk something through while it’s fresh in my mind.’

‘No worries, mate,’ Detective Munro said. ‘If it helps with this case I’m all yours. It’s been on my mind for nearly ten years now. What is it?’