The most vocal was an excitable-looking young fellow who was pushing at the nearest policeman’s arm. ‘It’s another one, don’t you see? Another victim!’ he bellowed. ‘Why won’t any of you listen?’

I touched him on the arm. ‘We’ll listen.’

So we did. And quite a tale Mr Thursday had to tell. That was his name: Edmund Thursday. And he’d been sniffing around a strange story that had to do with a place called Sweetville and its proprietor.

‘Mrs Winifred Gillyflower,’ he said as we walked purposefully over the slimy cobbles. ‘An astonishing woman. A prize-winning chemist and mechanical engineer. So why … ’

‘Why has she decided to open up a match factory in her old home town?’ I agreed.

‘And there’s something very odd about that place,’ Thursday continued. ‘A mill which never actually seems to produce anything? A chimney that never blows smoke?’

At that, the three of us looked up at the great red-brick chimney that loomed over the gates to Sweetville. It was indeed soot-free, and not a wisp of anything rose from its tip.

Our next stop was the Municipal Morgue. We gazed down on the corpse that had been fished from the canal. A young woman, her expression fixed and dreadful. Her skin waxy and luminous red.

‘Same as the rest,’ breathed Thursday. ‘All dead from causes unknown and their flesh … glowing.’

Now I don’t know if you’ve had many dealings with morgues – most of you only visit once and not in the best of circumstances – but this was a particularly nasty specimen. And the same could be said of its chief denizen, who seemed to take an unhealthy relish in his job.

‘Like something manky in a coal cellar,’ he cried. ‘They keep turning up in’t canal. The Crimson Horror!’

‘Ooh! Good name,’ I grinned (couldn’t help myself). ‘That’s good, isn’t it? The Crimson Horror! Cool!’ Then I did my best to calm down and look serious. ‘Wonder what it is?’

I’d put on some cotton gloves as it seemed wise to avoid contact with whatever the Crimson Horror was. I whipped out a magnifying glass from my capacious pockets (great word ‘capacious’. Wonder where I picked that up?) and bent low to gaze into the dead woman’s eyes. I saw something there and let out a low whistle.

Clara’s bright eyes widened. ‘Well?’

‘Do you know the old Romany superstition, Clara? That the eye of a dead person retains an image of the last thing it sees?’

‘Nope.’ Her face cracked into a puckish grin that wasn’t quite suitable to the occasion. ‘Why don’t you tell me about it?’

‘If you insist.’

‘I’ve heard of such a thing,’ said our friend Thursday. ‘Tommy-rot, of course.’

I was outraged. ‘Tommy-rot? Tommy-rot? Not.’

‘Not?’

‘Not tommy-rot. Not if the chemical composition of the whole body has been massively corrupted.’