Doolan nodded. ‘According to this old polisman, what happened was that a fellow called Olocher was due to be hanged for murder and rape in the old prison on Corn Market. But he took his own life before the hangman got him. This “Dolocher”, as the locals called him, was supposed to be his ghost, prowling the streets.’

‘Come on, Stephen,’ Swallow laughed, ‘this is bullshit. What’s it got to do with what we’re dealing with now? Ghosts don’t batter people’s heads in with fencing posts or kick them half to death with hobnailed boots.’

Doolan shrugged. ‘Well, it didn’t end there, Joe. On the night that Olocher took his own life, one of the soldiers on duty at the prison was found bloody and unconscious at his post. When he came around he said he’d been attacked by a monstrous black pig.’

‘So this was how “the Dolocher” story came about?’ Mossop said sceptically.

‘Hold on. It got more complicated,’ Doolan said.

Swallow raised an eyebrow. ‘I can’t imagine how.’

‘Here’s how,’ Doolan resumed his narrative. ‘The attacks went on over a period of a year or so. Always the same. This fellow would emerge, attack a woman in a quiet location and beat her badly. But there was no sexual assault or robbery. Then he’d scarper.’

‘Doesn’t say much for the beat men,’ Mossop commented. ‘Sure in those days didn’t they have bobbies on every corner?’

Doolan grinned. ‘And if my memory serves me right, a lot of them would be so addled with drink they wouldn’t see Ali Baba and the forty thieves going by. Here’s what happened. A miserable winter night like this. A young blacksmith has been drinking in a public house in Francis Street. It’s pissing rain and he has to walk home to Pimlico. He hasn’t a coat or a hat, so he spots a woman’s cloak hanging behind the door. He borrows it from the landlord’s wife and sets off. It’s got a hood on it, so he pulls that over his head and off he goes out into the rain. Somewhere near St Catherine’s, up on Thomas Street, he’s jumped on by this fella who must have thought he was a woman because of the cloak and hood. But he’s got his blacksmith’s hammer on his belt and he lashes out and knocks this fellow to the ground.’

‘Go on,’ Mossop said, engrossed by the narrative.