Inside were dozens of typewritten pages. I flipped through them, trying to find something to tell me what this file was about; why it was in Lady Bailey’s possession. Finally, I found a page covered in drawings, strange angular parts, labelled with tiny numbers and letters. My eyes widened. It was something to do with the military.

I didn’t hear her footsteps until it was too late.

Lady Bailey stepped into the room. Her tanned face drained of its colour when she saw me holding those papers.

‘I knew it.’ Her voice was thick with shock. ‘I knew it.’

‘Wait.’ I dropped the file, holding my jacket closed with one hand, concealing the napkins beneath. ‘Wait, it is not what you think.’

‘Who are you?’ She was frightened, backing towards the door. ‘Who sent you here?’

‘No one.’ I took a step towards her. ‘Please, I can explain—’

‘Help!’ she cried, whirling around. ‘Bouzid!’

I threw myself after her, dragging her back with one hand, shoving the door closed and turning the key with the other. In the confusion, the bundle of napkins and pins fell from my jacket, scattering across the floor. She was struggling, shouting for Bouzid even as I tried to cover her mouth, shaking with panic.

‘Listen!’ I begged, over her shouts. ‘Please listen, I’m not – I’m a woman!’ I grabbed at her face, trying to meet her eyes. ‘I’m a woman. Look!’ I gestured at the floor.

For a long moment she only stared at me, breathing hard. Then her eyes flicked to the pins and napkins scattered about our feet. I was about to take my hand away when there was a hammering at the door.

‘Madame Hilde?’ Bouzid sounded alarmed. ‘Madame, are you all right?’

I looked into her eyes. Please, I mouthed, and released my grip.

‘I am fine, Bouzid,’ she said, her voice trembling. ‘Fine. I thought I saw a scorpion but it was only an old stocking.’

Through the door I could hear Bouzid’s breathing. He must have run up the stairs.

‘Are you sure, madame?’ he asked after a moment.

‘Quite sure, thank you.’

There was a pause. ‘Madame, I do not wish to trouble you, but I cannot find del Potro. I did not see him leave the house. Monsieur Langham was very clear that he—’

‘I sent del Potro to town.’ Our eyes locked as she spoke. ‘He is running an errand for me.’

‘Very well, madame.’ The reply sounded reluctant.

‘Thank you, Bouzid.’

Neither of us moved until we heard his footsteps retreat down the stairs. Then Hilde pushed me away. Her eyes were clear, her expression icy.

‘Explain.’

I swallowed down nausea.

‘I’m a woman.’ I forced the words out. ‘And I needed …’ I gestured at the sanitary napkins, my cheeks burning.