‘Shit, it’s good to see you back here,’ she said, as they started down the corridor.

‘Steady on. I’ve just been summoned, not invited,’ said Erika, feeling nervous and excited.

‘Well, Marsh is freaking out,’ Moss explained.

‘That’s what happens when you let outside parties dictate an investigation,’ said Erika.

They reached the door to Marsh’s office. Moss knocked and they went straight in. Marsh was pale and standing over his computer, watching the breaking news running across the BBC News website announcing that Marco Frost had been released.

‘Thank you, Detective Moss. DCI Foster, please sit.’

‘I’d like Moss to stay, sir. She’s been working on this whilst I’ve been—’

‘I’m aware of your, investigations.’

There was a brisk knock at the door and Marsh’s secretary poked her head round. ‘I’ve got Sir Simon Douglas-Brown on the line, says it’s urgent.’

Marsh pushed his hand through his short hair and looked harassed.

‘I’m in an important meeting here, please relay that, and I’ll call him back asap, thanks.’

The secretary nodded and left, closing the door.

‘I’m your important meeting?’ asked Erika. Marsh came round to his desk and sat. Erika and Moss each pulled up a chair.

Marsh attempted a smile. ‘Look, DCI Foster – Erika. What has happened is unfortunate. I admit you may have been treated unfairly, and I will address this properly in due course. However, we find ourselves suddenly in the midst of a crisis. We’re on the back foot here. I need all the information and insights you have from your alternative investigation.’

‘Which, I hope, will now become your priority investigation?’

‘I will be the judge of that. Just tell me everything you’ve got,’ said Marsh.

‘No,’ said Erika.

‘No?’

‘Boss. I’ll tell you everything, and I’ll outline my theories, when you’ve returned my badge and reinstated me as SIO on this investigation.’ Erika sat back and stared at Marsh.

‘Who do you think you are, to come in here—’ he started.

‘Okay. I’ll leave you to your chat with Sir Simon. Say hi from me.’ Erika got up to leave.

‘What you’re asking is near impossible. You’ve got a serious allegation against you, DCI Foster!’

‘I call bullshit. Assistant Commissioner Oakley was acting on orders from Simon Douglas-Brown to remove me from this case. Little Matthew Norris has been in and out of youth detention for years. He’s assaulted several social workers and, I’ll repeat, at the time I hit him, his teeth were latched into the back of my hand. Now if that’s what this whole case swings on, then fine, but you’ll be waving goodbye to someone who can catch this guy. And of course, I’ll repeat this to the press, because I won’t go quietly.’

Marsh ran his fingers through his hair.

‘Sir, Marco Frost has just pulled together an alibi and made you all look like a bunch of bumbling comedy policemen. Didn’t DCI Sparks think to do a few background checks? I mean for God’s sake. CCTV from a newsagent! Oh, and I’ll also make sure that the press know there’s a killer still out there on the loose thanks to you, DCI Sparks, and of course the sleek fox himself, Assistant Commissioner Oakley.’

Marsh looked as if he were going to explode. Erika stared at him, not looking away.

‘Put me back on the case and I’ll catch this bastard,’ she said.

Marsh got up and went to the window, looking out at the bleak January landscape. He turned. ‘For fuck’s sake. Okay. But you are on a very short leash, do you understand, DCI Foster?’

Moss gave Erika a small, triumphant smile.

‘I understand. Thank you, sir.’

Marsh came and sat back down. ‘Well, go on, give me your insights.’

‘Okay. Let’s go public with this. Launch a fresh appeal, and if you can pull some strings, let’s get a television reconstruction going. We’re going to face flack for Marco Frost, sir, and you need to be ready to bombard the press with all the things we are doing, so they concentrate on that, not all the things that we didn’t do.’

Marsh looked at Erika. She went on, ‘We’ve already celebrated once that we caught the killer. We can’t do it again unless we really do catch him. So let’s get ahead of the news cycle. Make George Mitchell our main focus. Flood the press with the image of him with Andrea . . . We also need a scapegoat. The press will want to see that someone is paying for this fuck-up. And I know just the person.’