‘How comes he used the same bullet and shit?’ said Eddie.

‘Some things he can’t help,’ said Denise. ‘He’s a narcissist. He believes he’s ultimately powerful. The rituals he can’t change. He wants to be known, they are part of this identity, a uniform so that he can express this self.’

Harper looked up to the sky. ‘He needed a name that allowed him to hide his identity but also to display what he was.’

‘Sturbe,’ said Denise. ‘A Nazi serial killer.’

‘Exactly. He wears the name like a confession.’

‘Meaning?’ said Eddie.

‘Meaning, people want to show what they’ve done, so he’s wearing the badge — the serial-killer name. Like some sick joke.’

‘It’s unbelievable.’

They stared at each other, a horrible truth dawning. Harper looked from Denise to Eddie. ‘Tell this to no one. Not another soul. If our killer is a cop, then we’ve got to stay one step ahead of him — and that means keeping our communication tight.’

‘How do we find him?’ asked Denise.

Harper smiled.

‘What you got, Tom, what you thinking?’

‘If it’s a cop, then he’s listening in. He’s got access to case information. You know what we do?’

‘No.’

‘We use the same lure on him that he’s used on others.’

‘What’s that?’

‘The lure of authority.’

‘How?’

Harper sat down on the hood of his car. ‘We’ve got to frighten him into believing we do know his face or are about to. I guess that’s what he did with Capske. I guess he had something to sell. I guess he told Capske that he wanted to put things in the past with Lucy. We do the same. We lure him to us.’

‘What’s the plan, big man?’ said Eddie.

‘We go back in. We claim we’ve found something. A roll of film — that’s it. A roll of film from Lucy Steller’s apartment, dated according to her journal on some trip and labeled Yellowstone. It might be enough of the truth to get him interested.’

‘Yeah,’ said Eddie. ‘She was a good photographer. Used 35mm film. She had lots of photographs of animals from that trip. No reason why there wasn’t another film.’

Harper nodded. ‘We make all this known, we send the film to the photographic lab, then we lie in wait. And then he’ll come to us.’

Chapter Ninety-Six

North Manhattan Homicide

March 14, 8.33 p.m.

The plan had been set. They didn’t even tell Lafayette the truth. They only wanted the three of them to know. Any more added extra layers of doubt. A single offhand word, the smallest indication that it was a fraud and they were dead in the water. And that meant Lucy and Abby were also dead.

The evidence was sealed in a brown paper evidence bag. Harper brought it into North Manhattan Homicide after a further visit to Lucy Steller’s apartment.

He threw it down on the table and called to Denise, ‘Hey, we’ve found something that might give up the clue to this boyfriend.’

‘What have you got?’ said Denise. The team listened in.

‘We’ve got a roll of film. Lucy used an old 35mm camera. She liked to take shots. This is dated the last week of May last year — anything in the journals?’

Denise nodded and moved towards her desk. The other members of Blue Team started to draw in.

‘What is it?’ asked Garcia.

‘Film from Lucy Steller’s place. Dated. Could have shots of the killer,’ said Harper.

‘Jesus Christ,’ said Garcia, ‘and it’s just been sitting there all this time.’

‘Exactly.’

Denise rushed back over with an open journal. ‘That’s fantastic,’ she said. ‘Lucy spent the whole week with this guy in Yellowstone. This is dynamite.’

Harper banged the table. ‘We might just have him. Let’s get this down to the photographic lab, see if they can get us something.’

Harper made sure that the team spoke about the new evidence via email, radio and phone. He had no idea who the killer was or how and when he was listening, but things were getting increasingly tense so he presumed the killer had some direct line.

Harper, Kasper and Levene made their way down to the Forensic Unit’s photography labs. They checked in the evidence and walked through the corridors.

‘We need to stick with the evidence,’ said Harper. ‘If he comes, it has to be tonight. Tomorrow would be too late if we had the film.’

‘What about me?’ said Denise.

‘I want you to sit in the parking lot, keep an eye on who’s coming and going. Try to give us some warning.’

The three of them walked to the photographic lab and looked into the room. ‘That’s the in-tray over there,’ said Harper. ‘In thirty minutes that’s where our lure will be sitting.’

Chapter Ninety-Seven

Lock-Up, Bedford-Stuyvesant

March 14, 9.15 p.m.

The killer threw open the door of the lock-up and went inside. Several dogs were around his feet. He stared into the cell where Lucy was lying and snarled, ‘You hid things from me!’

Lucy turned and shivered. ‘I didn’t do anything on purpose,’ she cried out.

The dogs ran into the room and darted up to the Plexiglass and the door of the cell. They could smell the new intruder and sense their master’s anger. The killer crossed to the cell and smashed the Plexiglass with his fist. ‘Think, Lucy, or I’ll cut your veins and let these dogs in.’

‘Think about what?’

‘Me, Lucy — images, pictures, videos of me.’

‘I… there weren’t… you made me destroy them.’

‘I thought I did, but you lied — you had more.’

‘No.’

‘Think, Lucy. You have three minutes to let me know what was on that film.’

‘What film?’

‘Yellowstone. Our trip. What was on that film.’

‘I…’

‘Three minutes.’

The killer left and the dogs continued to circle and bark and jump up against her cell.

A moment later, he returned with a large package. He heaved it into the corner. It was a white powder. A chemical with a big hazard sign emblazoned on the side.

‘This is going to end badly, Lucy,’ he shouted. ‘They think they’ve got me cornered, but I’ve got something in store for them.’

‘What is it?’

‘Ammonium nitrate, Lucy.’

‘What for?’

‘You’ll find out one way or another.’

The killer left again and returned with another sack of the same white granules. He hauled it across to the corner. Lucy was staring, petrified. He left again and returned with two bags of nails and threw them on the ground next to the sacks.

‘I didn’t take any pictures of you. You didn’t allow me.’

‘Secret pictures, Lucy. Did you take any secret pictures?’

‘Only pictures of the park, and the marmoset and the moose. Not you. I promise.’

‘Not good enough. One minute and they’ll eat you alive.’

The killer brought in two three-foot pipes that had been sawn down. He threw them to the side, then shut the door.

‘Things are changing quickly, Lucy. The world is changing quickly too. It’s not enough to live, you have to make a difference, leave a legacy. I could’ve gone on for years, but things change. They want this to end badly? Well, that’s what it’s going to do.’

‘I can’t help,’ she said.

The killer marched across to the door and grabbed a large German Shepherd by the scruff of its neck.

‘Let’s see how honest you’re being.’ He opened the bolt and entered the cell. The dog saw Lucy. She was weeping and crying and shaking. The German Shepherd barked and bared its teeth.

The killer kicked the door shut and moved across, holding the dog firmly. ‘Now, Lucy, what was on that film?’

He moved the dog’s snapping jaw close to Lucy’s face. The teeth flashed and the bark was high and persistent. She shook and held her hands to her ears.

‘You!’ she shouted. ‘A picture of you!’

The killer moved back. ‘You were always a liar and a coward. What faith did you ever show me? None. I loved you so much and you gave me nothing, and now this. You betray me to the cops.’