Could he lie? At least about this? What was the point? He had to tell Rathbone that he had burnt the letters which implicated him-falsely. And there could be others saying that.

“That I did know at the time,” he replied. “I was executor of his will. He must have trusted me.”

Rathbone did not stay his hand at all, although the reluctance, the hurt at having to do it was in his voice. “Could you have taken this money yourself?”

“I don’t know! I suppose so. I can’t remember.” Monk sat forward, staring at the floor. “All I can see clearly in my mind is her face, his widow, telling me he was dead. We were in a very ordinary house, small and neat. I didn’t have the money, but I don’t know if I did something with it. I’ve racked my mind, but I just don’t remember!”

“I see,” Rathbone said gently. “And if Dundas were innocent, as you thought at the time, then was the truth that there was no fraud or that someone else was guilty?”

“I think that’s the difference,” Monk said, straightening up slowly and meeting Rathbone’s eyes. “Sixteen years ago there was definitely fraud. The grid references on the survey map were altered. If it wasn’t Dundas, then it was someone else, possibly Nolan Baltimore-”

“Why?” Rathbone interrupted. “If Dundas profited personally, why would Baltimore have forged a survey report?”

“I don’t know. It makes no sense that I can see,” Monk admitted, defeated again. It closed in on him on every side. “But I don’t believe there was fraud this time. The track was rerouted, but Dalgarno didn’t own the land. If there was illegal profit, then it was bribery in order to change the route and not divide farms or estates. And placed as they are, anyone could have done that out of a sense of preservation of the land, without being bribed to.”

Rathbone stared at him, his face very grave. “Monk-what you are saying is that Dalgarno had no reason that you know of to kill this woman. If he had no motive, and no one saw him do it, then there is no evidence to tie him into the crime at all.”

“There is a little,” Monk said slowly, very distinctly, hearing the words drop like stones, irretrievable. He must tell Rathbone all of it. “There is the paper Katrina Harcus left accusing him. But she also left one which, on the face of it, accuses me. And the button.” Now it would be impossible to retract. Rathbone would force him to tell the whole truth.

“Button?” Rathbone frowned.

“She died with a man’s coat button in her hand.”

“Torn off in the struggle? Why the devil didn’t you say so?” Now Rathbone’s face was keen, his eyes alight. “That ties him in completely-motive or not!”

“No, it doesn’t,” Monk said flatly, even at this awful moment aware of the bitter humor of it.

Rathbone opened his mouth to speak, then sensed something deeper and beyond words, and said nothing.

“I met her in the Botanic Gardens earlier in the day,” Monk went on. “She was very distressed, and still passionately convinced that Dalgarno was guilty. We more or less quarreled about it, at least that is what it would appear to be to any onlookers, and there were many.”

Rathbone leaned forward a little across the desk, concentrating intensely.

Monk felt hot, and then cold. He was shivering. “She grasped at me, as if to demand my attention. Then, in pulling away she tore the button off my coat. It was my button in her hand.”

“Several hours later? When fighting with her murderer?” Rathbone said softly. “Monk, are you telling me the whole truth? If I am to defend you, I need it.”

Monk looked up at him slowly, dreading what he would see. “I came to ask you to defend Dalgarno,” he said, ignoring Rathbone’s surprise. “I think he may be innocent. Either way, I need him to be defended to the best of anyone’s ability. If he hangs, I have to be certain, beyond any doubt at all-reasonable or otherwise, that he killed her.”

“I am more concerned about keeping your neck out of the noose,” Rathbone said earnestly. “You knew this woman, you were seen to quarrel with her the day of her death, and your coat button was in her hand. And you didn’t tell me what happened to the letters which incriminated you.”

“I took them,” Monk told him. “Runcorn asked me to show him the rooms where she lived. I saw them before he did. I took them, and burnt them when I got home.”

Rathbone let out a long sigh. “I see. And to whom were these letters written?”

“Someone called Emma, but I don’t know anything else, except that she did not live in London. I went back”-he saw Rathbone wince, and ignored it-“and looked for more, an address book, but I didn’t find one.”

“Were they regular correspondents?”

Monk’s voice was hoarse. “I don’t know!” He did not mention the diary. No one had heard about it, and he clung to the tiny thread of hope that somehow it would still tell him something about Katrina which could provide a link, however fragile. And there was something of her dreams in it he wanted to protect. Perhaps if he were honest, that was it.

“I see,” Rathbone repeated softly. “And you are afraid your actions will hang a man who may be innocent.” That was not a question. He knew Monk well enough for it not to need to be.

Monk looked at him steadily. “Yes. Please?”

“He may have his own barrister already,” Rathbone warned. “But I will do everything I can, I promise you.”

Monk started to say “You’ve got to,” and realized how foolish that was. He was asking a favor for which he could not pay, perhaps an impossible one. “Thank you,” he said instead.

Rathbone smiled slightly, like a moment’s sun on a winter landscape. “Then let us begin. If Dalgarno did not kill her, and you did not, then who did? Do you have any idea at all?”

“No,” Monk said simply. It was the bare truth. He realized how very little he knew about Katrina Harcus. He could have described her to the minutest detail-her hair, her face, her remarkable eyes, the way she moved, the inflections of her voice. He could have told Rathbone what she had worn almost every time he had seen her. But until the day of her death he had not even known where she lived, let alone where she came from or anything of her daily life, her family or her past.

Rathbone tightened his lips for a second, then with an effort forbore from making any comment on Monk’s gullibility. Perhaps if he considered it, he knew as little about some of his own clients. “Well then, the first thing you can do is find out everything else you can about her, and as rapidly as possible,” he said bleakly. “Go wherever it takes you, but report to me every day.” He knew he did not need to emphasize that.

Monk stood up. Rathbone had been light in his condemnation, saying nothing of criticism or blame, but Monk knew him well enough to be aware of his thoughts. He felt as crushed by the mere fact of them as if they all had been put into speech.

Rathbone handed him the funds he would need.

“Thank you,” Monk accepted, hating it. Whether Rathbone would get any of it back from Dalgarno was still an open question, but Monk could not afford to refuse. He had no idea where his search would take him. Not only would Dalgarno’s life depend on it, but his own conscience, his identity, and if things came to the worst, his life too. If it seemed Dalgarno would be convicted, then he would have to tell the court of the paper he had found at Katrina’s rooms, and destroyed, and show them that the coat button was his. Then how could even Rathbone save him from the rope?

And yet he was innocent. Perhaps Dalgarno was also.

“I need to start with Dalgarno himself,” he said aloud. “Get me an interview with him.”

The clock had struck nine by the time Monk stood in the Newgate cell, Rathbone sitting to the side in the only chair. Dalgarno, pale and unshaven, paced back and forth restlessly, his face already haggard from the shock of realization that ahead of him lay the possibility of the gallows.