We reach the open sea and the sailors drop the ropes to the barges, and reef the sails. A little breeze comes up and the sails fill and then the timbers creak as the wind takes the boat and we start to plough through the blue water with the waters singing along the prow. Izzy and I have always loved sailing and she forgets her fear and comes and stands with me at the side of the boat, looking over the rail for dolphin in the clear water. There is a line of cloud on the horizon like a string of milky pearls.

In the evening, we heave to off the port of Southampton where the rest of Father’s fleet is at anchor, waiting for the command to join us. Father sends a little rowing boat to tell them to come, and we wait, wallowing a little in the swirling currents of the Solent, looking towards land expecting to see, at any moment, a moving forest of sails, our wealth and pride and the source of Father’s power – the command of the seas. But only two ships appear. They come alongside us and Father leans over the side of our ship as they bawl to him that we were expected, that the Rivers’ son, Anthony Woodville, with his family’s cursed foresight rode like a madman with his troop to get here before us, and that he has commanded the crews, arrested some, killed others; but at any rate he has all of Father’s ships, including our brand-new flagship the Trinity, in his grasping hands. Anthony Woodville has the command of Father’s fleet. The Rivers have taken our ships from us, as they took our king from us, as they will take everything we own from us.

‘Go below!’ Father shouts furiously to me. ‘Tell your mother we will be at Calais in the morning and that I will come back for the Trinity and all my ships, and Anthony Woodville will be sorry he stole them from me.’

We will sail all evening and all night, running before the wind in the narrow seas to our home port of Calais. Father knows these waters well, and his crew have sailed and fought over every inch of these deeps. The ship is newly commissioned, fitted out as a fighting vessel but with quarters worthy of a king. We are sailing east before the prevailing wind and the skies are clear. Isabel will rest in the royal cabin on the main deck, I will stay with her. Mother and Father will have the large cabin beneath the poop deck. George has the first officer’s cabin. In a little while they will serve dinner and then we will play cards in candlelight which flickers and moves with the roll of the ship, then we will go to bed and I will sleep, rocked by the rise and fall of the waves, listening to the creaking of the timbers and smelling the salt of the sea. I realise that I am free: my time in service to the queen is over, completely over. I will never see Elizabeth Woodville again. I will never serve her again. She will never forgive me, she will never hear my name; but equally I will never again have to bear her silent contempt.

‘The wind’s getting up,’ Izzy remarks as we are taking a stroll around the main deck before dinner.

I raise my head. The standard at the top of the sails is flapping wildly, and the seagulls that were following the wake of the ship have wheeled away and gone back towards England. The little pearly clouds strung out along the horizon have massed and now lie grey and thick, like feathers.

‘It’s nothing,’ I say. ‘Come on, Iz, we can go into the cabin. We’ve never had the best cabin before.’

We go to the door that opens onto the main deck but as she puts her hand on the brass lock the ship dips and she staggers and falls against the door, which yields suddenly, making her tumble into the cabin. She falls against the bed and I scramble in behind her and get hold of her. ‘Are you all right?’

Another big heave of a wave sends us tottering to the other side of the little room and Izzy falls against me and knocks me against the wall.

‘Get to the bed,’ I say.

The floor rises up again as we struggle towards the bed and Isabel grabs the raised edge. I cling to the side. I try to laugh at the sudden swell that made us stagger like fools, but Iz is crying: ‘It’s a storm, a storm like I said!’ Her eyes are huge in the sudden gloom of the cabin.

‘It can’t be, it’s just a couple of big waves.’ I look towards the window. The clouds that were so light and pale on the horizon have darkened, and lie in black and yellow stripes across the sun, which is itself growing red and dark though it is still the afternoon.

‘Just clouding up,’ I say, trying to sound cheerful though I have never seen a sky like this in my life before. ‘Shall you get into bed for a rest? You might as well.’

I help her into the swaying bed but then the sudden drop of the boat into the trough of a wave, and the smack of the impact as it hits the bottom, throws me to my knees on the floor.

‘You come in too,’ Izzy insists. ‘Come in with me. It’s getting cold, I’m so cold.’

I heel off my shoes and then I hesitate. I wait and it feels as if everything is waiting. Suddenly, everything goes still as if the world has suddenly paused, as if the sky is silently waiting. The ship falls quiet, becalmed on an oily sea, and the wind that was blowing us homeward, steadily east, sighs as if exhausted and ceases. In the calm we hear the sails flap and then hang still. Everything is ominously horribly quiet.

I look out of the window. The seas are flat, as flat as if they were an inland marsh and the ship wallowing on silt. There is not a breath of wind. The clouds are pressing on the mast of the boat, pressing down on the sea. Nothing is moving, the seagulls are gone, someone seated on the crosstrees of the main mast says ‘Dear Jesus, save us’ and starts to scramble down the ropes to the deck. His voice echoes strangely as if we were all trapped under a glass bowl. ‘Dear Jesus, save us,’ I repeat.

‘Take down sail!’ the captain bellows, breaking the silence. ‘Reef in!’ and we hear the bare feet of the crew thundering on the decks to get the sails taken in. The sea is glassy, reflecting the sky, and as I watch it turns from dark blue to black and starts to stir, and starts to move.

‘She is taking a breath,’ Izzy says. Her face is haunted, her eyes dark in her pallor.

‘What?’

‘She is taking a breath.’

‘Oh no,’ I say, trying to sound confident but the stillness of the air and Isabel’s premonition are frightening me. ‘It’s nothing, just a lull.’

‘She is taking her breath and then she will whistle,’ Izzy says. She turns away from me and lies on her back, her big belly rounded and full. Her hands come out and grip either side of the beautifully carved wooden bed, while she stretches her feet down to the bottom of the bedframe, as if she were bracing herself for danger. ‘In a moment now, she will whistle.’

I try to say cheerfully: ‘No, no, Izzy . . .’ when there is a scream of wind that takes my breath away. Howling like a whistle, like a banshee, the wind pours out of the darkened sky, the boat heels over and the sea beneath us suddenly bows up and throws us up towards the clouds that split with sickly yellow lightning.

‘Close the door! Shut her out!’ Izzy screams as the boat rolls and the double doors to the cabin fly open. I reach for them and then stand amazed. Before the cabin is the prow of the ship and beyond that should be the waves of the sea. But I can see nothing before me but the prow, rising up and up and up as if the ship is standing on its stern and the prow is vertical in the sky above me. Then I see why. Beyond the prow is a mighty wave, towering as high as a castle wall, and our little ship is trying to climb its side. In a moment the crest of the wave, icy white against the black sky, is going to turn and crash down on us, as a storm of hail pours down with a rattle that makes the deck white as a snowfield in a second, and stings my face and bare arms, and crunches beneath my bare feet like broken glass.

‘Close the door!’ Izzy screams again and I fling myself against it as the wave breaks on us, a wall of water crashes down on the deck, and the ship shudders and staggers. Another wave rears above us and the door bursts open to admit a waist-high wall of water which pours in. The door is banging, Isabel is screaming, the ship is shuddering, struggling under the extra weight of water, the sailors are fighting for control of the sails, clinging to the spars, hanging like puppets with flailing legs, thinking of nothing but their own fragile lives, as the ship rears, the captain screaming commands and trying to hold the prow into the towering seas, while the wind veers against us, whipping up enemy waves that come towards us like a succession of glassy black mountains.

The ship reels and the door bangs open again, and Father comes in with a cascade of water, his sea cape streaming, his shoulders white with hail. He slams the door behind him, and steadies himself against the frame. ‘All right?’ he asks shortly, his eyes on Isabel.

Isabel is holding her belly. ‘I have a pain, I have a pain!’ she shouts. ‘Father! Get us into port!’

He looks at me. I shrug. ‘She always has pains,’ I say shortly. ‘The ship?’

‘We’ll run for the French shore,’ he says. ‘We’ll get in the shelter of the coast. Help her. Keep her warm. The fires are all out, but when they are lit again I’ll send you some mulled ale.’

The ship gives a huge heave and the two of us fall across the cabin. Isabel screams from the bunk. ‘Father!’

We struggle to our feet, clinging to the side of the cabin, hauling ourselves up on the side of the bunk. As I pull myself forwards I blink, thinking I must be blinded by the flashes of lightning outside the cabin window, because it looks as if Izzy’s sheets are black. I rub my eyes with my wet hands, tasting the salt of the waves on my knuckles and on my cheeks. Then I see her sheets are not black, I am not dazzled by the lightning. Her sheets are red. Her waters have broken.

‘The baby!’ she sobs.

‘I’ll send your mother,’ Father says hastily and plunges through the door, fastening it behind him. He disappears at once into the hail. Now and then the lightning shows the hail as a wall of white, smashing against us, and then it is black again. The black nothingness is worst.

I grab Isabel’s hands.

‘I have a pain,’ she says pitifully. ‘Annie, I have a pain. I do have a pain.’ Her face suddenly contorts and she clings to me, groaning. ‘I am not making a fuss. Annie, I am not trying to be important. I do have a pain, a terrible pain. Annie, I do have a pain.’

‘I think the baby is coming,’ I say.

‘Not yet! Not yet! It’s too early. It’s too early. It can’t come here! Not on a ship!’

Desperately I look towards the door. Surely my mother will come? Surely Margaret will not fail us, surely the ladies will come? It cannot be that Isabel and I are clinging to each other in a thunderstorm as she gives birth without anyone to help us.

‘I have a girdle,’ she says desperately. ‘A blessed girdle for help in childbirth.’

Our chests of things have all been loaded into the hold. There is nothing for Isabel in the cabin but a little box with a change of linen.

‘An icon, and some pilgrim badges,’ she continues. ‘In my carved box. I need them, Annie. Get them for me. They will protect me . . .’

Another pain takes her and she screams and grips my hands. The door behind me bursts open and a wash of water and a blast of hail comes in with my mother.

‘Lady Mother! Lady Mother!’

‘I can see,’ my mother says coldly. She turns to me. ‘Go to the galley and tell them they must get a fire lit, that we need hot water and then mulled ale. Tell them it is my command. And ask them for something for her to bite on, a wooden spoon if nothing else. And tell my women to bring all the linen we have.’

A great wave tosses the boat upwards and sends us staggering from one side of the cabin to the other. My mother grabs the edge of the bed. ‘Go,’ she says to me. ‘And get a man to hold you on the ship. Don’t get washed overboard.’

At the warning I find I dare not open the door to the storm and the heaving sea outside.

‘Go,’ my mother says sternly.

Helplessly, I nod and step out of the cabin. The deck is knee-deep in water, washing over the ship; as soon as it drains away another wave crashes on us, the prow climbs and then crashes, shuddering, as it falls into the sea. For sure, the ship cannot take this pounding for much longer, it must break up. A figure, shrouded in water, staggers past me. I grab his arm. ‘Take me to the ladies’ cabin and then the galley,’ I shriek against the shrieking of the wind.

‘God save us, God save us, we are lost!’ He pulls away from me.

‘You take me to the ladies’ cabin and then to the galley!’ I scream at him. ‘I command you. My mother commands you.’