‘Cherry,’ he gasped, heaving at the horse’s unresisting bulk until his joints cracked and his muscles tore and screamed with protest. And all the time the waters tugged and tugged at him, trying to pull his feet from under him and sweep him away to drown too.

‘God damn you, Rosa!’ His breath sobbed in his chest. His face was wet with river water and sweat and tears. ‘You’ll not die. Hear me? You’re not to die!’

He braced his feet against a rock in the torrent and heaved again at Cherry’s warm, dead weight, her blood running down over his shoulders and swirling into the water in a crimson slick.

She shifted – or maybe it was the pike in the river bed. Something gave a minute amount, and when he felt under the water for Rosa’s body, it didn’t come free but it moved.

Heat flooded back into his numb fingers and he heaved again at Cherry’s side, bracing his shoulders against her ribs and scrabbling for Rosa beneath the churning red water.

She moved again, an inch or two further from beneath Cherry’s hind quarters. One more heave – and she slid free with a rush so that he stumbled and almost fell into the current. Only his grip on Cherry’s bridle saved them both, and then he struck out for the bank, hauling Rosa in his wake, a drowned black rat.

At the bank he pulled her on to the muddy shore, heaving her clear of the tugging waters, and leant her body gently against the twisted roots of a tree. She lay there, painfully still, painfully white, her head at a strange, unnatural angle. But when he put his ear to her breast he could hear a beat and a wet gurgle – or thought he could. He willed her to cough – but she didn’t. He would have given anything for a thimbleful of witchcraft. No matter if it damned him to hell for all eternity, he would have paid the price if it meant he could save her. But he was powerless – and so was she.

For a moment Luke stood frozen in indecision. Then he began scrambling up the bank towards the bridge. At the top he shaded his eyes, looking after the riders. They were almost gone. Only one rider and horse stood in silhouette on the ridge: Sebastian. He would have known that beautiful thoroughbred anywhere and the arrogant set of the rider’s shoulders. Sebastian could save her. He was a witch, wasn’t he?

‘Knyvet!’ he bellowed, the words whipped and torn by the autumn breeze. Sebastian turned his head as if he’d heard something, but wasn’t sure what. ‘Knyvet!’ Luke shouted again, his voice cracking with the effort. ‘Come back! There’s been an accident. Rosa – she’s dying!’

For a moment he thought Sebastian had heard him. His horse took two steps downhill, towards the river.

‘Knyvet!’ he screamed, the words tearing in his throat. ‘For God’s sake, help!’

But then the horn sounded from the other side of the ridge, its long note drifting in the breeze, and Sebastian’s head turned to its siren call. Luke almost saw the shrug of his shoulders inside the beautifully cut jacket. And then he was off, away over the brow of the hill, and far out of reach.

Luke buried his face in his hands. They were covered in mud and Cherry’s blood.

He was completely alone. He couldn’t go after the riders – they were on the other side of the river and he had no way to cross it. And by the time he had galloped back to the house to fetch someone she would be dead – if she wasn’t already.

It was up to him.

He slid back down the bank, his fingers grabbing at roots and branches to stop his fall, and stumbled on to the little muddy shore where Rosa’s body lay. Her face was utterly, starkly white. Her hat had gone and her wet red hair straggled loose across her shoulders, its fire doused.

‘Rosa,’ he said very softly, his voice hoarse and broken from his efforts to call Sebastian. ‘Rosa, can you hear me?’

She said nothing – or nothing he could hear above the roar of the stream. But he thought he saw her ribcage move, and when he put his ear close to her face he realized she was breathing, or trying to. It was a horrible wet, bubbling sound, and as he drew back he saw there was blood on her lips.

‘Oh Jesus.’ He had never felt so helpless. He’d once watched a man drown in his own blood like this – a shiv between his ribs after a pub fight. And he’d felt a kind of detached sorrow. But it was nothing like this. The man had entered the fight of his own free will and lost. It was nothing to do with Luke. This – this was different. This was Rosa, dying in his arms, because of his actions.

Her breath bubbled again, poppy-red spatters on her blue lips.

What could he do? He searched his memory frantically – and a memory came – of Phoebe fainting in the bar one night and Miriam loosening her corsets to let her breathe.

He began to tear at Rosa’s habit. It buttoned up the front – hundreds of damn slippery bone buttons that his cold fingers fumbled and lost. But at last he had it open – and as he peeled back the wet black layers his heart seemed to stop.

The snowy-white stock beneath was scarlet with blood.

Where was it coming from? He ripped at her blouse, his fingers wet now with her blood, small mother-of-pearl discs scattering into the mud. There was a silver locket, slick with blood and he pushed it roughly aside. Beneath her blouse was some kind of chemise – God damn it – why so many layers? At last beneath that was her corset. It fastened with hooks and eyes and tied at the top with a pitiful pink ribbon. The bow was soaked in blood.

He put his hand to the laces, ready to tug it apart – then he stopped. Somehow he couldn’t bring himself to undo it. Her small white breasts rose and fell above the stiff edge, as she struggled painfully for breath, that horrible gargling sound bubbling inside her lungs. But all he could think of was her nakedness beneath – the violation of tearing apart her clothes as she died beneath his hands.

Don’t be stupid, a voice snarled in his head. Much she’ll care about her virtue when she’s as dead as her horse.

He set his hands to the fastenings and wrenched them savagely apart.

What was beneath brought bile to the back of his throat and sent a cold rush of horror prickling across the back of his skull and down his spine. For a moment his vision seemed to fracture and break and he swallowed. The force of the fall had snapped one of the whalebones in her corset, and the sharp edge had stabbed clean through the fabric, puncturing the pink tender skin beneath, sliding between her ribs and into her lung.

As he watched, Rosa dragged another breath and blood and air bubbled from the wound.

This was completely beyond him. She was drowning in her own blood – and there was nothing he could do.

What have I done?

You did what you had to do, lad. And now it’s over.

But it was not over. Not as long as she dragged breath after painful breath. Not as long as the blood bubbled at her lips.

He could finish it here. He could drive the whalebone home up into her heart. Then he could take the body back, his face wet with tears, and sob out his explanation: he told her not to go for the bridge, she wouldn’t listen, she was mad to catch up . . .

But he couldn’t. Crumpled white at his feet, her red hair trampled in the mud, she was no longer a witch but just a girl – a girl whose life was ebbing away as he watched.

He couldn’t kill her – not now, not ever. He’d known that from the moment he plunged into the river in a desperate attempt to undo what he’d done. Perhaps even before that, in his heart of hearts. He’d pushed this far in spite of himself, in spite of his misgivings, in spite of the weight around his heart every time he thought of his task and her death.

He should have felt even heavier now – for if she did not die, then he must. If he saved her life he was only betraying his Brothers and condemning himself to death. He should have felt full of dread and horror at what was to come as he watched her chest rise and fall with every painful breath.

But he did not. He felt only a fierce determination that she would not die, not if his actions could save her.

‘Rosa,’ he said, though he did not know if she could hear. His voice was hoarse with tears and shouting. ‘Rosa, can you hear me? This is going to hurt, but I’ll get you out of here, I promise. And someone at the house’ll be able to heal you.’

He put his hands beneath her armpits, the black habit gaping, and he heaved.

As her body slithered up the bank she gave a rattling gasp that might have been pain, or shock, or just the mechanical effect of her ribcage lifting with the pull.

‘I’m sorry.’ He gritted his teeth and pulled again, her body slipping up the rutted, muddy bank, her boots knocking against tree roots and stones. ‘I’m sorry.’

At the top he laid her on the grass bank and put his forehead against hers, her cold flesh chill against his hot sweating skin.

For a minute he knelt there, feeling his heart pounding, and the weak pointless tears scratching at the back of his eyes.

Then he put his arms around her, beneath her armpits and her knees, and very carefully, as carefully as he could, he picked her up, holding her against his chest, trying not to disturb the piece of whalebone sticking out of her lung. She was not heavy, in spite of the soaked habit that trailed on the grass. Without the drag of her soaked clothing she would have been no burden at all.

He began to walk, stumbling over tussocks and molehills.

‘Don’t die,’ he found himself whispering in time with his trudging steps and thumping heart. ‘Don’t die. Don’t die. Don’t die.’ Then, as he stumbled again, ‘Damn.’

What had he done?

Her cheek was cold against his chest – and he could not tell if her body was cooling, or if it was just the contrast with his own body, hot from toiling across the rutted field. He turned through the gap in the hedge into the lane where the going was easier, but he was panting now, his breath coming hoarse and hard, and Rosa felt twice as heavy as when he first pulled her into his arms.

‘Don’t die.’

Was she still breathing? There was fresh blood on her lips but that might just have dribbled out as he carried her. His heart was thumping so hard he could not feel any pulse from her.

‘Don’t die.’

Saints in heaven – how could he ever have thought she was light? His arms were ready to tear from their sockets. His legs felt like wool. He almost tripped as a rutted puddle barred the way across the road and the cold water soaked his legs, but he pushed on grimly. There was nothing else he could do.

‘Don’t die.’

At last – the gate into the Southing drive. He stumbled on to the gravel, crunching across the wide expanse in front of the house with legs that trembled and staggered up the steps to the drawing-room French windows, the closest entrance to the house. He had no hand free to pound on the glass so he kicked with his boots instead, pounding at the frame so that the doors shook against the wood.

‘Let me in!’ he bellowed. ‘There’s been an accident; she’s dying.

There was no answer. He had a sudden, horrible realization – the whole house was out hunting. The servants had all been despatched to take the hunt breakfast to the spinney. What if there was no one here?

‘Open up!’ Luke roared in despair. ‘For the love of God, please, please somebody come and help me.’

And then he saw a figure making its way slowly across the drawing room.

‘Open up!’ he shouted. ‘Hurry!’

It was a girl – one of the servants or one of the family, he couldn’t tell, but why in God’s name was she moving so slowly, so deliberately? She was picking her way through the furniture as if she was walking in a mist.

‘Are you deaf?’ he cried, his voice close to a sob. ‘Open up, I said. It’s Miss Greenwood, she’s dying.’

‘I’m not deaf.’ He heard the voice through the glass as the girl reached him, her beautiful cornflower-blue eyes looking up at him as she struggled with the lock. ‘I’m blind.’

The door gave and he stumbled into the room, muddy boots and bloody clothes leaving a trail of filth and blood on the Persian rug.

‘What’s happened to her?’ the girl asked, her voice sharp. ‘I can feel she’s nearly gone.’

‘She had—’ Luke’s voice stuck in his throat. How could he say an accident, when it was anything but?

He put Rosa down carefully on the chaise, her body a crumpled rag, her magic a thin wisp of flame so slight he could hardly tell it was there. The girl knelt beside the chair, her head bowed. Her fingers hovered over Rosa’s face, touching her bruised blue skin, and then trailed down to where the whalebone stuck like a stiletto dagger between her ribs.