‘I just want cold air,’ she said. ‘I’m not going kill myself.’

Erika dressed and came downstairs to the large plush lobby, which was empty save for a bleary-eyed receptionist. He looked up from playing solitaire and gave her a nod.

She relished the sensation as she hit the freezing air outside. There was a row of benches along the front of the building. She chose the first, and pulled a cigarette from the packet, lighting up and exhaling a stream of smoke into the night sky. She shivered, shaking the dream off her, and forced her thoughts back to the investigation.

Maybe this would be that case. The one that got away. Every police officer was haunted by an unsolved case. She flicked her ash on the gravel and there was a miaow as a large black cat appeared from under the bench and rubbed itself against her legs.

‘Hello,’ she said, leaning down to stroke it. The cat purred and strutted off to a couple of little dishes under one of the bay windows. It lapped at some water and then sniffed the bowl next to it, which was empty.

Linda Douglas-Brown came to the front of Erika’s mind. Linda the cat lady. So much evidence linked back to her. Linda was supposed to meet Andrea that night at the cinema, but didn’t. She’d watched the film with David. They knew that much, but what had happened afterwards? Linda, and her obsession with cats. What did she know about Linda? Was she a victim in life? She was obviously not a favourite with her family. She was bitter and envious. She could have killed Andrea, but what about the other women? The prostitutes who had been involved with Igor? Linda knew of Igor, she’d met him. What if she also knew that Igor had killed the three prostitutes? She could have seized the opportunity to make Andrea’s murder look like a copycat killing? Copycat. Linda the cat lady.

It went round in Erika’s mind. Yet Linda didn’t have a cat. Peterson had asked her in the interview if she had a cat. She had answered him weirdly – not right now – and a look had passed across her face, a strange look. Erika hadn’t picked up on it at the time, but now it blared out at her.

Erika went back up to her room, where she dressed quickly, and, after passing the disinterested lad on reception for the second time, she drove over to Lewisham Row Station. It was now just after five in the morning. She wasn’t familiar with the night desk sergeant, but he signed out the keys to her for the Douglas-Brown house.

The roads were quiet as she drove over to Chiswick. The office buildings loomed tall and empty as she navigated her way through Elephant and Castle, crossing the Thames at Blackfriars Bridge and then following the river along the Embankment. The view of the water was dimmed by a low fog, which turned blue as the dawn broke.

Erika placed a call to Moss, but she got her answering machine.

‘Hi, it’s Erika. It’s coming up to five-thirty. I’m just on my way over to the Douglas-Brown house. Something is bugging me about Linda. I want to take a look at her bedroom. If I’m not back by seven, interview her again – and get Peterson to lead; she seems to have taken a shine to him. Get her talking about cats; I know it sounds mad but I think there’s something there, I can’t put my finger on it . . . She’s cat crazy, but she doesn’t have a cat . . .’

Her phone gave three bleeps and then cut off.

‘Shit!’ Erika cried, looking down at her dead phone. She’d barely been back at the hotel long enough to charge it.

She arrived on Chiswick High Road. She tucked her phone in her pocket and parked on one of the back streets, realising she would have to be quick, and would need to travel back on the underground to have any hope of making it to the station before the twenty-four hours expired.

70

The Douglas-Brown house sat resplendent at the end of the cul-de-sac, dominating the street like a polished, buttery block. Mist hung in the air, and the street lights blinked off as she reached the house. The front gate was well-oiled and opened soundlessly. The bay windows stared back at her blankly. She went to the front door and pressed the bell, hearing it ring deep from within the house. A moment passed, then she started to try the bunch of keys in the front lock. The third key she tried opened the door. She listened for a moment and then came inside, closing the door behind her.

She made for the hallway, past the grandfather clock with its swinging pendulum, and into the vast steel and granite kitchen. It was still and immaculate. Copper pots hung from a frame above a large black granite island, and the back wall was floor-to-ceiling glass. Beyond, she could see the landscaped garden. A blackbird landed on the smooth grass, but seeing Erika move inside, it took flight.

Erika came back out and climbed the sweeping staircase up to the second floor, moving past smart, neutral guest rooms, a marble bathroom, until at the end of the corridor, at the back of the house, Erika found Linda’s room. The door was closed with a small sign saying: Welcome to Linda’s bedroom, please knock before entering. Under it, and almost obliterated with crossings-out, was written: cos i might not be wearing any knickers! Erika couldn’t help but smile, and thought it must have been David. Little brothers liked to tease. She opened the door and went inside.