‘First I have something to show you.’ She led him by the hand to the sitting room where she had left Klara’s locket, with the hidden compartment open. ‘Edie found this. I don’t know if you can see that clearly, Tom, but it shows two sets of initials – GR and AH.’

‘Good God. Geli Raubal and—’

‘Precisely. Don’t say it.’

‘Did Edie understand the significance?’

‘I don’t know. She said nothing. But then she is very discreet.’

Wilde closed the locket carefully.

‘Whatever happens, we must make sure Bodie Cashbone never sees this.’

*

Wilde awoke in the dark. Johnny was crawling on top of him, crying. He looked at his watch and saw that it was five o’clock in the afternoon, then hugged his son and rubbed his back until the crying subsided.

He put Johnny back to bed and went in search of Lydia. She was carrying a fresh glass of water from the kitchen to Klara.

‘How is she?’

‘The same.’

‘Did you get any sleep?’

‘I’m ashamed to say I slept like a top. Some nurse I am. Would have slept through like you, but Johnny woke me demanding food.’

‘Thank you. I’m sorry to do this to you again, but I’ve got to go out.’

‘And leave me in this madhouse isolation ward? Thanks, buster.’

‘I need to see Eaton. He’s the only one who can help us.’

The snow flurries had gone and the sky was clear but the cold was biting. In Trumpington Street, outside the college, he scanned the road for Cashbone, but there was no sign of him. Scobie told him that Mr Philip Eaton had arrived and was presently taking tea with the master.

‘Put a call through to him, Scobie. Tell him I’ll be in my rooms if he’d like to join me there.’

Fifteen minutes later, Wilde heard the uneven steps of Eaton on the staircase. He carried a stick and paused at every step before moving on upwards. Wilde met him halfway and offered his arm to help him.

‘No, damn it, I can do it on my own.’

Wilde shrugged and left him to it.

‘Whisky?’ Wilde said when Eaton had made it to the top.

‘Bit early for me, but what the hell . . . ?’

‘You’ve got to help me, Eaton. Two women dead, murdered in cold blood, and Cashbone won’t move an inch from his entrenched position on the girl.’

‘Nor will you by the sound of it.’

‘That’s because I’m in the right – and you know it.’

‘This has all become a great deal larger since the two murders. My friends in Five are crawling all over the house at Harkham – you realise it was theirs, not Six’s, I imagine?’

‘I gathered as much.’

‘Analysis suggests the bullets used to kill both Mrs Kemp and Frau Somerfeld came from a British-made Sten gun. What does that suggest to you?’