I gave some consideration to whether a woman would be strong enough to smash a head against a rock in the way that Rose-Marie’s had been. I supposed it was possible, but I couldn’t imagine women sorting out their differences quite that directly. I’d have thought supposedly intelligent women would never get to that point in the first place, and if they felt the need to take action, it would be a damned sight more subtle – a bit of sabotage, maybe, or muck-racking, something with a bitchiness factor about it. But murder over stepping on toes or a few research hours? It seemed a bit of a stretch. Mind you, there were plenty of murderesses rotting in prison to prove me wrong. I would be very interested to hear Penny Hawkins’ slant on the situation.

Smithy must have been thinking along similar lines. ‘We’ll be talking to Dr Hawkins later in the day,’ he said.

‘For heaven’s sake, don’t tell her I mentioned anything.’ Simpson looked very uncomfortable with the idea of being identified as the nark.

‘You don’t need to worry. I do know how to conduct an interview, Professor.’

I turned to stare. Smithy’s frostiness surprised me, but seemed lost on the prof. Although Smithy was the one asking the questions, I blurted one out to allay any possible awkwardness over the comment. ‘So what exactly was she researching?’

This time it was the professor turning to look at me. It was as though he had only just registered my presence. He gave me a searching look and a smile which left me feeling warm and thinking again of that earlier incarnation of James Bond. ‘She was researching drug-delivery systems, specifically looking at a new way of administering insulin.’

‘Sounds interesting.’ Smithy’s fine brand of sarcasm again. I had to turn away and pretend to look at some equipment to hide my smile.

‘It was very important research which looked like it would have very useful commercial applications and potentially save lives. Unfortunately, I can’t go into it further, as it’s commercially sensitive.’

Like a couple of detectives were going to spill the beans. Smithy took the reins again. ‘What were you doing on Friday evening?’

The prof looked a little taken aback at the directness. ‘I would have been here, in my office. I think I was going over another doctorate student’s thesis. I worked to about six, then met up with some friends at the Staff Club for a few drinks. That’s what we do every Friday night. After that I went home.’

‘And do you have anyone who’d be able to corroborate that?’

The prof’s eye’s narrowed, but to his credit, he maintained an air of calm.