Nessa heard her sister moving through the house, the creak of floorboards overhead, toilet flush, sink running, the front door clicking shut. Beside her Ronan slept, his lips parted, a soft snore on the breath in. Later she told the detectives she heard the car start on the street. The last sound that connected Deena to the world. Something could have happened right there outside as Nessa rolled back toward Ronan’s warm body, burrowed deeper under the comforter and slept.

Maybe an hour after she heard the car, Nessa walked down toward the museum for the papers. She hadn’t worn a scarf or hat and the wind blowing from the river was sharp, stinging her face. Afterward, every detail of that morning became crystallized, refined through repetitions into a series of stills. The naked trees. Her breath making small quick clouds in the air. The patch of ice at the corner of Aspen. The empty sidewalk. The blank grey of it all, everything bare, giving away nothing.

Back at the house she woke him. They drank coffee and read the papers. She repeated something Howard Dean had said about the war in Iraq. Ronan agreed. The Da Vinci Code was still number 1 on the bestseller list. Ronan handed her an article from the New York Times and tapped the headline. It was about the death of Kitty Genovese in Queens. Next month marked the fortieth anniversary. Nessa vaguely remembered the story from a college class. The bystander effect. Thirty-eight people had heard the woman being attacked and no one had done anything.

She watched Ronan dress and pack his bag. One of his socks was black, the other navy blue, his hair sleep-matted at the back. She wished he wasn’t leaving. She listened to the sound of running water in the bathroom and was thinking about the word ablutions when her phone rang. It was Molly: Deena hadn’t shown up for her 7 a.m. shift.

Nessa opened the curtains and looked out the window at the empty space below, where Deena parked her car.

Later the detectives would tell her that Molly McKenna first called her at eight forty-five. When Ronan came back in, ready to go, Nessa was standing in the middle of her room, still holding the phone.

They drove to the train and talked about the things that might have held Deena up – a flat tyre, an accident, an appointment she forgot. Getting out of the car at Suburban Station, Ronan gazed up at the art deco facade. Nessa smiled because she knew he was about to tell her how much he liked it, for maybe the hundredth time. His hair was still flattened and she’d forgotten to tell him his socks were mismatched. Later she would remember watching him look up, and would hold that moment: the last time she was seeing him or anyone before she could never see anything the same again.

Back at the house she tried to read the New York Times article. Kitty Genovese’s brother said that he’d found it difficult to cope after her death and had enlisted in the Marines. All the time he was in Vietnam he had flashbacks about what had happened to his sister. He became obsessed with trying to save people.

The bare walls of Deena’s room were painted brilliant white. Everything was in its place. When they’d shared a bedroom at home, Deena’s side had been strewn with empty Coke cans, heaps of dirty clothes, stacks of books. Four years older but ten times messier. Nessa had had to patrol the demarcation line they’d agreed, kicking back wet towels and school kilts. But now Deena’s space was immaculate. If you start arranging my cans in the cupboard by colour we’re done, Nessa had joked when she’d moved in. On the bedside table, a black-and-white photograph of Ruby just after she was born softened the space. In it, Ruby’s head rests on Deena’s bare chest. It is their first moment together, Ruby’s small hand clutching a handful of her mother’s hair. Skin-to-skin, the midwife had said when she put Ruby on Deena’s chest.

Deena’s bookcase was organized by category. Nursing and anatomy on the bottom shelf; above were self-help guides on mental health, ways of rebuilding yourself, books about living with narcissistic men, books on motherhood. Neatly stacked beside them were the journals she’d endlessly scribbled in since high school. The month, the year recorded on the spine of each book, from the age of fourteen. Then the gap, 1999 to 2002, the years with Lucas. He’d taken those and Deena hadn’t been able to get them back. The rest of the shelves were lined with novels and poetry. One volume was balanced horizontally on top: Adrienne Rich, Dark Fields of the Republic – paper strips slipped in to mark the poems she returned to.

Deena had painted the wooden floorboards white too. The order and blankness had initially bothered Nessa, as if Lucas was still bossing Deena around from a distance, making her think she was messy, making her shrink. But she was beginning to understand Deena’s need to control her environment, to be hyper-structured about everything. Lucas had taken so much. The desperation to keep order was her resisting him and all the things he’d said to her about who she was: lazy, chaotic, crazy, whatever. Maybe having order was her way of telling herself she was not those things; maybe it was even a fuck-you. Standing in the emptiness of Deena’s room, the possibility first occurred to Nessa that her sister might never come back.

Nessa counted the scrubs hanging in Deena’s closet. She owned three – one wasn’t there. She had gotten ready for work. In the bathroom the hamper was empty. Her toothbrush sat in its holder. There was a framed card their mother had given Deena for graduation. A Dickens quote with a stethoscope spiralled around it: Have a heart that never hardens, and a temper that never tires, and a touch that never hurts. Deena had hung it in the bathroom. Probably because it was where she got ready every day, a reminder from her mother before she went in to the NICU.

Sometimes their dad called Deena if he wasn’t feeling well. She’d take his blood pressure. She’d bring her stethoscope and let Ruby listen too. Ruby would compare hearts. She’d place the chest piece against her own. Mine’s quiet, Grandad. Yours is noisy. Another time she’d listened to their two hearts and said, Mine’s winning. It’s faster.

Something must have happened at home. Deena was there, looking after him. Nessa ran downstairs to the phone.

Joey answered. He was in a hurry, couldn’t talk. But he said, No, Dad’s asleep.

He stopped at the news that Deena hadn’t shown up at work. He hadn’t talked to her since Friday.

I’ll come in, he said.

The John Garvey stencilled on the side of the truck was faded, nearly gone, the & Son slightly brighter. Plaster dust, wood shavings, paint, receipts stuffed between the windshield and dashboard; it was just like their dad’s trucks growing up. The familiarity steadied Nessa. Her phone rang as they merged onto the Parkway. Molly. Deena still hadn’t shown up. The parking garage near the hospital had four levels; they checked every one. The guy in the security booth scanned the camera footage. She hadn’t arrived.

They sat in Joey’s truck with the engine turning over, shivering, waiting for the air to blow hot. Nessa checked the time. One thirty. Six hours until Ruby would need to be collected from her weekend with Lucas.

Back at the house they went upstairs to Deena’s room. Joey stood in the middle of it, uncertain what to do. Nessa went into the bathroom and checked the medicine cabinet. Deena’s medication was there; beside it a bottle of Children’s Tylenol.

Joey, maybe something happened to Ruby. Why didn’t I think of that already?

Ruby was sick and Deena had gone over there. Everything made sense.

They decided Nessa should call Lucas, ask to speak to Ruby.

Joey sat next to her, leaning in so he could listen. She exhaled slowly as she dialled, trying to calm herself.

This is Nessa, she said when he answered.

Oh, hi Nessa. How are you?

Joey shook his head slightly at her. This was off. She and Lucas were never polite.

Can I speak with Ruby?

She’s a bit busy right now.

She made up something about Ruby’s fish having babies. He said nothing.

Just let me talk to my niece, Lucas.

Nessa? Ruby’s small voice.

Ruby! How are you?

Good. My grandmom’s here.

What? Their mother had died over a year ago.

Grandma’s there?

Not our grandma. Clover.

Nessa had never met Lucas’s mother. She wasn’t sure if Ruby had either. She didn’t think so.

Did your mommy meet her too?

How?

You didn’t see your mom today?

No. I’m at my dad’s.

Nessa watched Joey as she spoke. She could see the worry.