‘I am looking for Isabel Alvarez,’ I said, without preamble. If this man intended to be aggressive, I could return like for like. I would not let him intimidate me, however aggressive he appeared. Like him, I stood with legs apart and let my hand rest casually on the pommel of my sword.

‘And who are you?’ he said, in a tone that did not reflect our clearly different social status.

‘Her cousin, Christoval Alvarez,’ I said. I had no intention of revealing my true identity to this man, even if he was one of the family caring for my sister. Isabel herself, of course, would know me.

‘Have you proof of that?’ He spat, narrowly missing my foot.

I clenched my teeth. It was not this man’s place to demand such proof, but I did not intend to come to blows with him. Not if I could avoid it.

‘Naturally. Though I see no need for it.’ I put into my voice all the scorn of a Portuguese aristocrat speaking to a labourer. I would not be intimidated by this fellow. My indignation was burning in my cheeks.

I produced the passport Dom Antonio had provided me with. If this man was a supporter of King Philip of Spain, I was placing myself in great danger, but I must somehow gain access to my sister. However, here in this remote farm it was likely that the fellow took little interest in politics. If the Spanish invaders left him alone, he probably cared nothing, one way or another, who ruled the country. As my grandfather’s tenant, his obligations in rent and duty would be to him, rather than to the Spanish. He took the passport, stared at it in such a way that I knew he could not read, then handed it back to me.

‘You have read it?’ I said blandly, aware that he had not. ‘You can see that I am Christoval Alvarez, cousin of Isabel Alvarez, and I demand that you take me to her at once.’ I was pleased that my voice was firm, with all the authority I had a right to, as a member of his overlord’s family.

A look crossed his face which I did not like. A barely suppressed smile, a knowing smile. It gave me a brief stab of unease. With a jerk of his head he indicated to me to follow him round to the back of the house. We crossed the yard, which was no more than beaten earth, liberally scattered with dung. Broken farm tools, lengths of wood, dented buckets, and unidentifiable rubbish lay everywhere, so that I had to pick my way amongst the obstacles, though the way was so familiar to the farmer that he moved swiftly across the yard before halting before an open door. Like the front door, this one hung crookedly. It could be cold here in the mountains in winter. The January wind must find its way through the house, from the gaping front door to the back, with its icy fingers touching everything. My sister Isabel was living amongst this filth and squalor and misery?

The door on this side led directly into a kitchen roofed with beams so low the man had to stoop and I could only just stand upright. The girl I had seen before was slicing onions and wiping tears from her eyes. She was cutting straight on to a scarred table of pine, so old that it dipped in the middle like a sway-backed horse. A child of about four, naked from the waist down, was playing on the floor with what I thought at first was a furry toy, before I realised that it was a dead rat. A baby was lying directly on the dirt floor, half wrapped in a filthy blanket, moth eaten and frayed. It had fallen open and the baby was naked underneath it, a girl child. She stared up at me with wide, vacant eyes. The girl by the table was visibly with child again. This must be the farmer’s wife, but where were the older couple, the da Rocas to whom my sister had been entrusted? Were they too dead?

The man pointed at the girl chopping onions.

‘That is Isabel Alvarez.’

When we were very young, Isabel and I shared a bed. Our nursemaid slept in the adjacent room with the baby Felipe, so there was no one to stop us whispering together on the hot sleepless nights of summer. I cannot now remember all that we talked of, what pressing concerns occupied our minds in those days. I think we complained of minor injustices and comforted each other in our sorrows. I know that when my pet sparrow died, and I cried all night, Isabel put her arms around me and cried too. We must have had plans and dreams, but these are lost now from memory, except that I remember we were never to be parted, and if our parents should marry us to husbands who lived far apart, we would run away and live together in the magical forest of Buçaco, where we would build one of our secret houses, like the ones we built every summer when we stayed at the solar, only bigger, with carpets on the floor. That was a point of luxury Isabel always insisted upon: carpets from Turkey on the floor. I had my own requirements. I wanted to be sure it would have a place for dogs and horses. Isabel conceded that.

‘But they must not walk on the carpets,’ she said earnestly, and I promised that I would make sure they did not.

When you have shared every bath with your sister and laid your head on the same pillow every night, you come to know every detail of her body as well as your own. Isabel had a tiny mole behind her left ear, not much larger than the head of a farthingale pin, and sometimes I would tickle it to wake her in the morning. I stared now at this slovenly woman with her brood of children and knew she could not be my sister. Her eyes were dull and stupid. She must surely be older than seventeen. And yet, and yet . . . There was something in the curve of the cheek, the shape of the hand that held the chopping knife.

I stepped forward and lifted the lank, greasy hair away from the girl’s left ear. She flinched away, and the hand with the knife flew up towards me. I leapt back.

‘What are you doing!’ the man shouted, bounding across the room to me.

My heart was pounding painfully. Isabel would never aim a knife at me.

‘I know how to prove if this is indeed Isabel Alvarez,’ I said. I was breathing hard and I felt sickness rising in my throat. ‘Tell her I mean her no harm. Tell her to put the knife down.’

I do not know why I addressed him instead of her. Perhaps some instinct prompted me.

‘Do as he says,’ he said roughly to the girl, then took the knife from her hand and threw it across the table. The baby began to cry, and the boy – I saw now that it was a boy – stood up and sidled behind the man who, I suppose, was his father.

I stepped forward and cautiously lifted the girl’s hair again. Her whole body was tense with terror. The skin of her neck was dirty, but there, just below her hairline, was the tiny mole.

‘Oh, Isabel,’ I said, and I could not stop my tears, ‘Isabel, what has happened to you?’

Isabel looked from the man to me and back again, her lips slightly parted and that dull, hopeless look in her eyes. I had never seen such a look of utter despair.

‘You’ll get little sense out of her,’ the man said, with some complacency. ‘She can cook, a little, and keep my bed warm, but she is no good for anything else.’

‘What have you done to her!’ I turned on him, shouting. ‘She was beautiful and clever when last I saw her, at ten years old. Now I find her, barely seventeen, treated like a slave and bearing your brats.’

‘No blame to me,’ he said insolently. He leaned his shoulders against the bare stone wall and smiled again, that knowing smile. ‘She and her brother both fell ill when they were placed here in my mother’s care by Senhor da Alejo, seven years ago. The boy died and the girl developed brain fever. When she recovered she had become simple-minded, as you see.’

‘But surely my . . . my great-uncle came for her?’ I was losing the thread of my story and my pretended relationship with Isabel. ‘And why did your mother betray her trust by letting you take her as your whore?’ I was breathless with horror and confusion.