“Oh Maudie,” he said. He was trying for a bored, incredulous tone, I could tell, but he couldn’t quite pin it down. “What are you saying? You’re totally insane.”

“But that wasn't it, was it Matt?" I said. I could hardly speak, my mouth was so dry. "That wasn't what you had planned at all, was it?" I thought back to the sleeping pills he'd reminded me to get. I thought of how bitter the brandy he’d brought me had tasted.

"Were you trying to get me sectioned? Or was it more than that, were you trying to make me kill myself? Or were you going to do it for me?”

“Oh God, would you just listen to yourself?” said Matt. I could see beads of sweat caught like pearls in his stubble. “You’re completely insane, you’re mad.”

Jessica was looking back and forth, from Matt's face to mine.

“I’m not,” I said again. “If I’m mad, who’s that?” I gestured at Jessica. “Who’s that, then?”

Matt’s face flickered. “Who’s who?” he said, quietly. “Maudie, there’s no one there.”

I blinked. For a moment, I thought I’d misheard him.

“Don’t be stupid,” I said after a moment. “Don’t try that. You know she’s there. She’s there.”

He was looking at me quite steadily. “Who’s she?” he said. I could see Jessica’s head whipping back and forth as she switched her gaze between our faces. “There’s no one there.”

“You just talked to her! You just looked at her! You told her not to come here.”

“Maudie, for God’s sake,” he said. He was holding both hands up as if he were warding something off. “You’re frightening me now.”

“Stop it,” I said, my voice trembling. “I know what you’re trying to do.”

“Stop what?” he said. His voice had got suddenly gentler. “Maudie, you need help. You’re seeing things. There’s no one there.”

“There is!” I said, in what was not quite a shout. The sound made me start to cry, properly, and I heard myself sob with helpless fury. “She’s there, she’s right there, you were just talking to her, she’s there...”

Matt was shaking his head, quite slowly. The disgust was gone from his face: now he simply looked sad. He held out the brandy glass to me again. “Drink this,” he said. “You need to drink this. Don’t struggle anymore.”

I turned to Jessica. “I know you’re there,” I said, my voice vibrating so much I could barely understand myself. “This is just part of his plot, that’s all. You know that.”

"I’m here," she said. “You’re not wrong.”

I looked her, full in the face. I had to make her understand.

"So was he paying you?" I said. "Did he promise you a cut of the proceeds? Did he say he'd take care of you?"

Her eyes wavered and fell. I saw her fingers close in on one another.

"He told you that," I said. "I wonder what else he told you about me? Do you think he was going to let you just walk away with your money? When you're the only person who knows what he did?"

She looked up again at that and her eyes met mine, wide and horrified.

“Maudie, stop it,” said Matt. “Stop pretending. It’s embarrassing.”

I ignored him. "No one knows you exist, Jessica, do they? Who is going to miss you, if you disappear? Don't you think he knew that? He knows you're - you're totally dispensable. How long do you think you’d last, once he got what he wanted?"

I stopped speaking and for a moment the room was silent, save for the sound of our lungs labouring for air. Slowly, Jessica turned to Matt. He wasn’t looking at her; he hadn’t taken his eyes off me. Then, very slowly, she pivoted. She turned back and I saw her mouth something, I heard her whisper something. I think it was 'go'.

I didn't stop to think. My foot went up and out, connecting with the brandy glass in Matt’s hand. It went flying, a golden sheet of liquid, spread for a second in the air like a shimmering silk scarf. Then the glass hit the floor and shattered. In the same moment, I propelled myself forward, aiming myself between the two of them. My shoulder hit Matt’s arm and flung him backwards. I was at the hallway door. I was running down the corridor to the front door. I was free.

I was at the front door, scrabbling at the lock, when he grabbed me around the neck. I shrieked.

“Shut up,” he hissed. “Shut the fuck up, or I’ll kill you right now, right here.”

His arm was pressing on my windpipe. I clawed at his sleeve, gasping. He began dragging me backwards. I could hear my heels thumping and clacking uselessly on the wooden floor as I was pulled remorselessly back into the living room.

He stopped for a moment, panting. His hold around my neck had loosened and I dragged some air into my burning lungs. I was almost too frightened to think, certainly to speak, until I saw Jessica’s face. I couldn’t stop thinking of her as Jessica. She was biting her lip, looking at Matt and me. Her hand was at her throat again, holding onto the necklace that I’d bought her.

I managed to get enough air in to speak. “Jess – you - please help me. Please–”

Matt pulled me away. He started dragging me towards the doors of the roof terrace. I started to struggle even harder. I stopped clawing at his arm that lay like a bar of iron across my neck, the muscles tense as stone, and started flailing at anything I could, grabbing for a grip on something anywhere, on anything.

“Don’t fucking struggle,” said Matt, through gritted teeth. He sounded as if he were crying. “If you do, I’m just going to knock you out. Stop struggling –“

I barely heard him. I had my eyes fixed on her, on the fake Jessica. I tried to pour all my terror, all my despair into my eyes, every single bit of concentrated emotion into my gaze; as she’d once done for me, staring up at me from the street outside.

“Jessica,” I croaked. “Don’t let him do this-” She said nothing but her eyes were on mine. I couldn’t read her expression. My vision was beginning to fog.

My last sentence was cut off with a gasp as I was pulled through the open doorway to the roof terrace. A gust of cold wind blasted against my cheek.

“Straight over,” said Matt in a high, strange voice. He sounded hysterical; he was half-laughing, half-sobbing. “It won’t hurt, Maudie. It’ll be quick.”

The next moment, the rough concrete of the boundary wall was up against my chest and my head was being forced over the top of the wall. I heard the tinkle of glass as my knee hit the mirror that stood against the wall. I could see the street far below. It was going to happen, then. I was going to die.

“I’m sorry,” said Matt, crying. “It’s for the best. I’m sorry-”

I could feel him dip behind me and grasp me around the waist and I felt myself begin to rise. I couldn’t scream. My whole being was concentrated on trying to grip the wall, trying to stay alive for one second longer. The far-off road swung dizzily in my tear-filled vision. God help me.

The pressure around my waist suddenly slackened. At the same time, I heard Matt roar out. I was released; the swinging road vanished as I fell backwards away from the wall. My feet hit the floor and my knees buckled, but, oh God, I hadn’t gone over, I hadn’t fallen... I gulped in cold night air. My face was burning where the concrete had scraped it and I’d cut my knee on a shard of mirror glass. I turned round.

Jessica had dug her fingers into Matt’s eyes. She had her arms around his neck and was forcing his head back. Her teeth were bared in a desperate grimace; she looked as though she was laughing. As I watched, Matt’s fist caught her full in the face and he flailed backwards – I watched her nose spout blood and gasped involuntarily. She loosed her hold and dropped to the floor. Matt turned, snarling, his eyes streaming. I saw his fist come up and back as my own hand closed upon a long shard of glass. As his fist came down towards Jessica’s face, I drove the glass into the side of his neck.