Holmes nodded without taking his eyes off the boy. ‘Run away with you, where?’ he asked.

Peregrine Buttons looked at us and smiled. Mad, definitely mad, I thought. ‘Scotland. Or maybe Paris.’ His eyes glittered briefly at the image of this joyful thought.

‘Did you believe her?’ asked Holmes.

‘Of course.’

‘But she wanted something from you. She asked you to do something.’

‘The rings …’

‘Yes. You pawned Freddie Eden-Summers’ and Leo Vitale’s engagement rings for her with Piotr Flan across town at three a.m. He gave you twenty-five for the two,’ said Holmes. ‘But it wasn’t enough.’

‘Holmes,’ I whispered, ‘take this slowly.’

‘You are a magician! How can you know this?’ stammered Buttons, staring in horror at Holmes.

‘Not a magician, more like a bloodhound. I just came from Flan’s. What was this money to be used for?’

‘Holmes. The situation is precarious,’ I whispered.

‘Our train tickets. And a new start.’

‘But then?’ Holmes inquired. ‘Something went wrong.’

The young man wavered. He placed a foot on the railing.

‘Take your foot off there,’ cried Holmes.

The boy took his foot down and looked about dreamily. ‘“You belong with me, Perry,” she said. That was what she called me.’

‘That is very sweet,’ I said, hoping to distract him. Holmes gave me a sharp look and turned back to the boy.

‘Running away together – was this something you had planned?’

‘No. We had joked about it. But I never … I only dreamed …’ Buttons replaced his foot on the railing.

‘Step back from the railing, please,’ said Holmes sharply.

‘No. Stay away from me!’ The young man turned and looked down at the water.

Holmes moved to one side. I took that moment to look about to see if the police might be visible yet. I saw no one. Had the message gone astray? The rain hissed down around us.

‘You returned with the money, and then what happened?’

Buttons suddenly doubled over the railing as if hit in the stomach. A sob escaped him. ‘Oh God! Oh God!’

Holmes took the opportunity to draw closer.

‘Pull yourself together, Mr Buttons,’ I said, trying to distract him by moving away from Holmes.

He made an effort and straightened, then crumpled again. ‘Oh, Dillie.’

‘Let me help,’ said Holmes. ‘You returned and found Dillie in your bed.’

‘By God, how do you know this?’

‘Mr Buttons, you remember why you came to me in the first place?’

‘Because you read of Mr Holmes’s particular reputation as a detective,’ I prompted.

Lightning flashed, lighting up the sky and the boy’s confused face.

‘You came back with the money,’ Holmes pressed on. ‘But something happened. Perhaps Dillie refused you. You quarrelled. You fought.’

‘No! No! But … she said the money was not enough. We would need more.’

‘For train tickets?’