“What are you going to do now?”

“I’m going to ask Anna Blake’s landlady a few more questions,” she said.

“Can I go with you?” he asked eagerly.

“I know you want to help, but I don’t think the Walcotts would be very happy to see you again.”

“Who are the Walcotts?”

“They own the house where Anna Blake lived.”

“Oh.”

“I’m just going to ask a few questions,” she explained. “Then I’ll take this new information to Mr. Malloy. And then, I hope, he will arrest the real killer, and your mother will be free.”

“What questions are you going to ask?”

Sarah wasn’t sure herself. “I’ll figure that out when I get there.”

To Sarah’s relief, the El wasn’t very crowded. The hour was later than she’d realized, and most of the workers had already made their way home. Sarah sat, staring blindly out the window at the buildings whizzing by, and tried to piece together everything she’d learned about that night. Anna had been home with Catherine and Mr. Walcott and maybe Mrs. Walcott, too. Mr. Walcott was sitting around in his shirtsleeves. Harold had come barging in. Mr. Walcott hadn’t wanted him there, but Anna Blake had enjoyed tormenting the boy. Harold had threatened her, and then he’d left. Anna had played checkers with Catherine until Catherine went to bed, well after dark. According to Catherine, Mrs. Walcott was probably angry with Anna, but she hadn’t said anything to Anna in Catherine’s presence. This meant she was either there when Harold came or returned home later.

After Catherine went to bed, something had happened, and Anna had gone out. Either she got a message from someone or she’d had a quarrel with Mrs. Walcott or maybe Mr. Walcott or both of them, and she’d left the house. Then she’d been stabbed at some unknown location. She’d been trying to get back home, but she’d fallen in Washington Square and died there before she could.

Sarah remembered what the coroner had said about Anna having been with a man shortly before she died. Could that man have been Mr. Walcott? Was that what she and Mrs. Walcott had quarreled about? Was that why Mrs. Walcott had lied about what time Anna left the house? And why had everyone lied about Mr. Walcott being home that night? The answer was obvious, and Sarah had a pretty good idea she now knew who the killer was. She should probably go straight to Malloy with the news, but she was afraid he wouldn’t act on it unless she had more than just a suspicion. She only needed one more piece of information, and she could get it from either of the Walcotts. If she could get them to cooperate without arousing their suspicions.

Night was falling as Sarah reached the house on Thompson Street. She’d miscalculated the time, forgetting how short the days were getting as October advanced. A light was burning in one of the front rooms at the Walcott house, however, so Sarah knew someone was home.

No one answered her knock at first, but she wasn’t going to give up, not when she was so close, so she kept on knocking. Finally, the door opened a crack, and half of a face peered out cautiously.

“Is Mrs. Walcott home?” Sarah asked when the person didn’t speak.

The door opened a bit wider, revealing that the person behind it was Mrs. Walcott. She was a far different Mrs. Walcott than Sarah had seen before, however. Instead of her extravagant wig, she wore a dust cap on her head, as women did to protect their hair from dirt when house-cleaning. Or when women who wore wigs wanted to relax from the weight of them and still not reveal the condition of their real hair. The cap fit closely, which meant there wasn’t much hair underneath. Probably, Mrs. Walcott was going bald for some reason, so she did not even go bare-headed in the privacy of her own home. And instead of one of her stylish gowns, she wore a simple housedress that was faded from many washings. Her face looked faded, too, as if strain had leached the color from it. The only thing that hadn’t changed about her appearance was her expression. She still looked cool and calm and more than a little condescending.

“What are you doing here at this time of night, Mrs. Brandt?” she asked. Her voice hadn’t changed, either. She was still cultured and precise.

“I happened to be in this part of the city, and I thought I would stop by and see how you’re faring. I also wanted to let you know how the investigation is going,” Sarah lied. “We have some new information.”

Mrs. Walcott looked past Sarah, as if expecting to see Frank Malloy. “Are you alone?” she asked in some surprise.

“Yes. As I said, I was in the neighborhood, delivering a baby,” she added, embellishing her lie to sound more plausible. “I thought it was still early enough to stop by on my way home. May I come in?”

“Certainly,” she said, stepping aside to allow her to enter. The house was as chilly as the street outside, and Sarah remembered Catherine Porter mentioning that Mrs. Walcott didn’t like to build a fire.

“Is Miss Porter in?” Sarah asked, pulling off her gloves.

Mrs. Walcott stiffened at the question and proceeded to close the door very carefully, not looking at Sarah. “No. No, she isn’t.”

Her reaction had been so odd that Sarah felt a frisson of alarm. “Is she all right?” she asked.

Mrs. Walcott managed a strained smile. “I’m sure I have no idea. Please, come in.” She led Sarah into the front parlor, the room where a lamp burned.

Mystified, Sarah followed her into the parlor and took the seat Mrs. Walcott indicated. The landlady sat down across from her, in front of the cold fireplace, and folded her hands demurely in her lap. She wasn’t wearing the mitts she usually wore, and she folded her hands tightly, as if she were ashamed of them or something. Perhaps she was. Perhaps that was why she wore the mitts in the first place.

“You said you had some news,” Mrs. Walcott said. “About Anna’s death.”

“Yes, I… Mrs. Walcott, I don’t know how to say this without sounding rude, but I’m afraid I have to ask you again if your husband was at home that night.”

Mrs. Walcott stared at Sarah for a long moment, as if trying to read her thoughts. “I am assuming that you believe he was, in spite of what I told you.”

“Yes,” Sarah said. “In fact, I now have very good reason to believe he was.”

Mrs. Walcott sighed and dropped her gaze. “I don’t suppose I need to lie anymore. Yes, he was here that night.”

“Why did you lie about it before?” Sarah asked.

Mrs. Walcott’s expression hardened, and her eyes were full of hatred when she looked up again. “I love my husband, Mrs. Brandt. I wanted to protect him. Anna Blake’s death was no great loss to anyone, and he didn’t really mean to kill her-”

“Your husband killed Anna?” Sarah cried, trying not to sound exultant at having proved her theory so easily.

Mrs. Walcott nodded, her entire body rigid with emotion. “I couldn’t bear the thought of losing him,” she said, pulling a handkerchief from her sleeve and dabbing at her eyes. “I knew he wasn’t always faithful to me, but… He could be so loving. I would have done anything to protect him.”

Sarah couldn’t help feeling compassion for this woman, even though she would never understand the kind of devotion that led a woman to lie for a man like that. “Has something happened to change your mind?” she asked gently.

“Oh, yes,” she said bitterly, her eyes bright with unshed tears. “You asked me if Catherine Porter was here. The answer is no, she’s gone. She and my husband left together.”

Sarah gaped at her. “You mean they ran away together?”

“So it appears. My husband had decided he could no longer stay in the city, you see. He was afraid that sooner or later your Mr. Malloy would figure out that he had killed poor Anna. He led me to believe he and I would go together, so I helped him with the arrangements. It was wrong, I know, but I couldn’t help myself. I would have followed him anywhere, you understand, but when I woke up this morning, he and Catherine were both gone. He left me a note… He was very unkind.” Her voice broke, and Sarah’s heart ached for her.