Lestrade leaned in close to Madame, sniffing her breath, then with a pointed look at Holmes, picked up one of her hands and smelled it. He smiled proudly. ‘You have gin on your breath, some kind of chemical on your hands – and your husband was soaked in it. A receipt for a one-way ticket through to Palermo was found in your hotel room, and … here …’ Lestrade leaned into her and plucked out a small white token which protruded from the pocket of her skirt. ‘Aha! Yes, just as I thought! Here is a token for a locker at Victoria. Will we find your packed valise in there, Madame?’

She stared at him in apparent confusion.

‘I wager we will,’ said Lestrade. He turned to Holmes triumphantly. ‘Two can play at your game, Mr Holmes. Sometimes, you see, things are best left to the professionals.’

‘Bravo, Lestrade. A remarkable chain of inferences, all based on solid evidence,’ said Holmes quietly. Lestrade beamed and nodded to his two men.

‘Except that you are entirely wrong,’ added my friend.

The room went silent. I became aware of the soft sobbing of Annie Duggan’s friend near the entrance.

‘Do you think so, Holmes? Let us see you prove it,’ said Lestrade, folding his arms across his chest.

‘This lady is in distress. Allow her to sit,’ I demanded.

Lestrade waved at his men to comply. Madame was returned to the chair. I moved to the lady’s side and patted her shoulder.

‘Try if you must,’ said Lestrade, ‘but you know you are beaten this time, Holmes.’

Holmes knelt down before the lady, taking both her hands in his. ‘Madame,’ he said gently, ‘what was your errand when you left the hotel?’

‘Dario sent me to pick up a velvet jacket he had made on Jermyn Street.’

‘Expensive tastes, as I said, Lestrade. What then, Madame Borelli?’

‘I returned to our hotel room. I stepped inside and it looked like a tornado had passed through. Then from behind someone put a cloth on my face, pressing, pressing. I could not breathe … a terrible smell—’

‘You smelled the petrochemical and the gin, but missed the third odour which lingers under the gin, Lestrade. The lady was chloroformed. The gin was applied to her lips later.’ He gestured politely towards the woman’s face.

Lestrade hesitated, then leaned in for a sniff.

‘Ah, well, possibly. But to what purpose?’ sneered Lestrade.

‘Obvious. She is being framed for a murder,’ said Holmes.

‘By whom? Who would want Borelli dead and his wife in gaol?’

‘Well, that’s the other little problem with your theory.’

Holmes strode over to the cauldron and opened the front hatch wide, so we all had a clear view of the blackened remains inside.

‘This body is not Dario Borelli,’ said Holmes.

Even I was surprised at this revelation.