‘Yes, sir,’ nodded Woolf.

‘And I’ll need a phone,’ added Erika. ‘If you could find something older, preferably with actual buttons. I hate touch screens.’

‘Let’s get started,’ said Marsh. He swiped his ID card and the door buzzed and clicked open.

‘Snotty cow,’ murmured Woolf, when the door had closed behind them.

Erika followed Marsh down a long, low corridor. Phones rang, and uniformed officers and support staff streamed by in the opposite direction, their pasty January faces tense and urgent. A fantasy football league pinned up on the wall slid past, and seconds later, an identical pin board held rows of photos with the heading: killed in the line of duty. Erika closed her eyes, only opening them when she was confident she had passed. She nearly crashed into Marsh, who had stopped at a door marked INCIDENT ROOM. She could see through the half-open blinds of the glass partition that the room was full. Fear crawled up her throat. She was sweating under her thick jacket. Marsh grabbed the door handle.

‘Sir, you were going to brief me before—’ started Erika.

‘No time,’ he said. Before Erika had a chance to respond, he had opened the door and indicated she should go first.

The incident room was large and open plan, and the two-dozen officers fell silent, their expectant faces bathed in the harsh strip lighting. The glass wall partitions on either side faced onto corridors, and along one side there was a bank of printers and photocopiers. Tracks had been worn into the thin carpet tiles in front of these, and between the desks to whiteboards lining the back wall. As Marsh strode to the front, Erika quickly stowed her suitcase by a photocopier which was churning out paper. She perched on a desk.

‘Morning everyone,’ said Marsh. ‘As we all know, twenty-three-year-old Andrea Douglas-Brown was reported missing four days ago. And what has followed has been a media shit-storm. Just after nine o’clock this morning, the body of a young girl matching Andrea’s description was found at the Horniman Museum in Forest Hill. Preliminary ID is from a phone registered to Andrea, but we still need a formal ID. We’ve got forensics on their way now, but it’s all being slowed down by the bloody snow . . .’ A phone started to ring. Marsh paused. It carried on ringing. ‘Come on people, this is an incident room. Answer the bloody phone!’

An officer at the back snatched it up and started to speak quietly.

‘If the ID is correct, then we’re dealing with the murder of a young girl linked to a very powerful and influential family, so we need to stay far ahead on this one. The press, you name it. Arses are on the line.’

The day’s newspapers lay on the desk opposite Erika. The headlines screamed out: DAUGHTER OF TOP LABOUR PEER VANISHES and ANDIE KIDNAP TERROR PLOT? The third was the most striking, with a full-page picture of Andrea under the headline: TAKEN?

‘This is DCI Foster. She’s joining us from the Manchester Metropolitan Police,’ finished Marsh. Erika felt all eyes in the room turn to her.

‘Good morning everyone, I’m pleased to be . . .’ started Erika, but an officer with greasy black hair interrupted.

‘Guv, I’ve been on the Douglas-Brown case, as a missing person and . . .’

‘And? What, DCI Sparks?’ asked Marsh.

‘And, my team is working like clockwork. I’m following up several leads. I’m in contact with the family . . .’

‘DCI Foster has vast experience working on sensitive murder cases . . .’

‘But . . .’

‘Sparks, this isn’t a discussion. DCI Foster will now be taking the lead on this . . . She’ll be hitting the ground running, but I know you will give her your best,’ said Marsh. There was an awkward silence. Sparks sat back in his chair and regarded Erika with distaste. She held his gaze and refused to look away.

Marsh went on, ‘And it’s mouths shut, everyone. I mean it. No media, no gossip. Okay?’ The officers murmured in agreement.

‘DCI Foster, my office.’

Erika stood in Marsh’s top-floor office as he searched through piles of paperwork on his desk. She glanced out of the window, which afforded a more commanding view of Lewisham. Beyond the shopping centre and train station, uneven lines of red-brick terraced houses stretched towards Blackheath. Marsh’s office deviated from the normal order of a Chief Superintendent. There were no model cars lined along the window sill, no family photos angled on the shelves. His desk was a mess of paperwork piled high, and a set of shelves by the window seemed to be used as an overflow, crammed with bulging case files, unopened post, old Christmas cards and curling Post-it notes covered in his small spidery handwriting. In one corner, his ceremonial uniform and hat lay draped over a chair, and on top of the crumpled trousers, his Blackberry winked red as it charged. It was a strange mix of teenage boy’s bedroom and high authority.