And now Cora could tell this was not news to the girl. She felt she had let down the charming Mr Butler. ‘I saw the red wound to the side of her head after he struck her. There was an umbrella in the way when the blow must have been struck. But he was holding on to her before and after the wound appeared. Is that helpful to you?’

‘Tell me more about the perp.’

‘Excuse me? The…’

The perpetrator, you said he was tall. How tall?‘

‘He was taller than the woman.’

‘How much taller?’

‘Hard to say. The umbrella was an impediment most of the time. And I suppose the way he held it made him very tall, but – ’

‘Do you think I’m very tall?’

‘Oh, my, yes.’

‘Are you even sure it was a man? Or did you assume that because you thought they were lovers?’

‘You’re quite right, of course. I shouldn’t have assumed that. I haven’t been very helpful, have I?’

‘Of course you have,’ said her young man, gallantly jumping into a breach of uncomfortable silence. He looked up and exchanged expressions with the young woman. His face said, Play nicely. And her face said, Why the hell not. And now the young woman smiled.

‘You were better than most. I have nightmares that any case will hang on an eyewitness. Eyewitnesses are never any good. Their testimony is the worst evidence you can bring into a court room. But you confirmed the scene of the crime. That’s useful. You placed the time of the murder, that’s helpful. You saw the first blood. I like that. All in all, a good job.’

And now the smile evaporated, and Cora could read nothing in the young woman’s face any more.

Charles leaned forward, still careful to include Cora in the conversation by not averting his lips as he spoke. ‘Mallory, do any of the suspects have dogs?’

‘Everyone in the building has a dog. Why?’

‘Cora tells me there was a dog running through the park that morning. He was dragging a leash. Maybe one of your suspects walked the dog that morning and then lost track of the animal while he was doing a bit of murder.’

Mallory turned to Cora. ‘You saw the dog?’

Cora nodded.

‘What was the breed?’

‘I’m afraid I couldn’t say. My glasses – ’

‘What size was it?’

‘Oh, a standard size, not awfully big or very small. I’m sorry, I can’t – ’

‘What color was it?’

‘I don’t remember, but I think it might have been dark – but not black, not that dark – maybe a brown dog.’

‘Maybe?’

She had no answer for that. She had underestimated the young woman, and now she was wondering if there had been a dog at all, or a pair of lovers. Could they have both been women? Might the dog have been -

‘Well now,’ said Charles, lurching once more into the silence. ‘You place a dog on the scene, and you’ve ruled out toy poodles and Great Danes.’

The young woman nodded. This was useful to her, which seemed to please Charles very much. Any fool could see he was in love with the girl. Well, at least he was happy. Good job. She had come to like this man.

When she rose, announcing that she must take her leave of them, he escorted her down in the elevator and handed her into a cab. He insisted on paying her fare to the driver. As she shook hands with him, she said, ‘You were born in the wrong century, my dear.’

When he returned to the apartment, it was difficult to miss the sharp knife lying on the coffee table next to the canvas duffel bag. As if she didn’t own enough weapons. First there was the very large gun which bulged under the blazer. She removed this now and took it into a back room. Then there was the gun that she ought to be carrying, the one the police department actually approved of. He supposed she kept that one at home. And last, there was Markowitz’s ancient Long Colt, which she kept in the desk of her office at Mallory and Butler, Ltd. He would never have pictured her with a knife.

He picked it up and turned it in his hand. On the reverse side of the blade was the crest of Maximillian Candle.

‘It’s probably none of my business,’ said Mallory, walking back into the room and nodding towards the knife, ‘but I wondered what was going on in the basement. I just came from there. The door was unlocked, and the partition for Max’s equipment was wide open.’

‘My fault, I left in rather a hurry. You didn’t by any chance pull that knife out of the target, did you?’

She nodded.

Charles stared down at the knife and forgot to ask what had brought her to the basement, so great was his surprise. It was the wrong knife of course. All the blades that came from the interior of the target were partial blades without points, and fixed to the mechanism. They could be pushed back into the compartments but not drawn out, and not with a full blade and a point.

When he had explained it to Mallory, she asked, ‘Could anyone else have been in the basement with you and Justin?’

‘Well, it’s possible, but I doubt it.’

‘Did you tell the parents what happened in the basement?’

‘Yes, of course. I called them from the office. It took me forty minutes to track them down to a cocktail party. The child had been in trauma. They had a right to know he was upset.’

‘Well, you also left the basement door open. Has the boy had time to go back and change the knives, the boy or one of the parents?’

‘But the front door of the building wasn’t unlocked. It’s self – ’

‘And we both know that a kid can bypass that security. How tough do you think it would be for an adult?’

‘I just can’t picture one of them – ’

‘Easier to picture that scenario than a knife flying through the air on its own. Someone has gone to some trouble here, and this is quite an escalation from flying pencils. This business has got to be cleaned up, and it’s up to you. I’ve got my hands full with a murderer.’

‘You truly believe someone in the Riccalo family is going to get hurt?’

‘Oh, sure. It’s coming. Count on it.’

‘There’s no supportable argument for that.’

‘So?’

So, when did logic ever interfere with her train of thought? It was her method first to settle upon a target hypothesis and then to move toward it with great velocity, and let nothing get between her and it.

An eye-blink ago, the space by Mallory’s feet had been empty, and now it was full of cat. Nose was picking up her bad habits.

‘Are you still planning to wrap up Amanda’s death by the twenty-sixth?’

She nodded. ‘If I don’t move on it now, I’ll lose him. If I string him out too far, he might get to a lawyer before I can nail him.’

‘Lucky for you, all three suspects are spending the holidays in town.’

‘If one of them had left town, I would’ve crossed him off the list.’

‘But logically – ’

‘Logic only works on paper.’

‘Jack Coffey seems to think – ’

‘You talked to Coffey? You didn’t tell him about the novel, did you?’

‘No. Why didn’t you tell him? Why all the secrecy? You work with these people.’ No, wait, fool. She doesn’t. She works alone.

‘A cop is leaking information. I’m not taking any more chances.’

‘But you’re taking terrible chances. Suppose you’ve underestimated the murderer. Coffey says you underestimate every – ’

Mallory’s posture was ramrod straight. Her chin lifted only a little.

‘I know this man. He cleaned that apartment over and over again. He cleaned things he couldn’t have touched. He had to be absolutely sure he wouldn’t miss anything. And so he can never be sure he didn’t miss something. He’s the only one who can tie me to Amanda Bosch, because he’s the only one who knows she’s dead, and that I was mistaken for her. He wants to run, but he can’t. He figures I know something, but he doesn’t know how much. It’s driving him crazy, me being here. Every message I leave on the computer puts him closer to the edge. He can’t leave. He was my prisoner the day I moved into this condo. He’s waiting for me to come and get him. Every knock on his front door is the end for him. When he can’t stand it any more, when he snaps, he’ll come to me. And I will pick that moment.’