"Even better, Yolanda. Because the police can tell me exactly what time you used it on Wednesday to get into the subway. What time and where."

"They can't do that," she said, getting angrier and more defiant.

"It's all computerized. I'll know exactly how long you were on the train. And we'll also be able to find out how many people were on whichever platform you were on when you say Laquon dragged you."

"Why does that matter?" Her head snapped around when she heard Ryan reenter the room with her sister.

"Because if you don't tell the judge the truth, you're going to be arrested."

Yolanda was crying now, clearly more afraid of her sister than of me. "But I told all of you I don't remember what happened."

"And I'm telling you that I don't believe that. If you weren't drunk or you weren't high or you weren't hit over the head with a baseball bat, you're the only one of us who knows exactly what happened last Wednesday."

I started to tell Wanda some of the inconsistencies between the story her sister had originally told the police and what she was saying today. I handed her the piece of paper with Laquon's name and beeper number on it, ringed with the hearts that Yolanda had drawn.

Wanda pinched the girl on the shoulder. "Why you be actin' all 'I don't remember this' and 'I don't remember that'? Why you be telling me you don't like this boy but you writin' down all his information? Girl, you ain't half as stupid as you pretendin' to be."

"I'll tell you what, Yolanda. The two of you can go down to Ryan's office and wait while he sends this MetroCard over to the transit office to be decoded and gets the information about your subway ride last week. I'm going to hang on to your weapon," I said, holding up the box cutter, "and we'll just toss your marijuana."

Wanda smacked her sister on the back of her head. "What you doing with-"

"Don't hit her again. Don't ever let me hear you laid a hand on her," I said. "And, Yolanda, if you decide there's anything about your story you want to change before you meet the judge, you tell Ryan as soon as you get down to his office."

"If I do, do I have to come back and see you again?" she asked, clearly anxious to avoid that possibility.

"Not if the information Ryan gets from the Transit Authority helps jog your memory."

"You mean, if I tell him everything I can just go home?"

"If it's the truth, yes."

Yolanda followed Wanda out the door before I could pick up the file and return it to Stewart. "I didn't know you could get all that information from MetroCards."

"That's what you're here to learn," Ryan said, winking at me. "Laquon and Yolanda-can't you just feel the love, Alex? I never saw you do the pocketbook trick before."

"Teenage girls carry half their lives in those things. The older women get, the more you can find in the handbag. Pills, condoms, diaries, weapons, love letters. I've broken more cases with a peek in the purse than everything I learned in law school. I'd guess that little Yolanda's probably half a hooker already."

"That's what Laquon claims."

"Well, if the subway records are more consistent with his story and you can't break her, bring her back up and we'll beep a few of her conquests. See what they can tell us about her."

Each MetroCard is encoded with a unique ten-digit serial number, which generates a fare-card history report with every use. It would tell me the time Yolanda went through the turnstile in one-tenth-of-an-hour intervals, what train station or bus she used, and even what her remaining balance was. I wouldn't have to be the sole judge of her credibility-the transit records would prove she had lied.

I walked Ryan and Stewart to the door and picked up my messages from Laura. "These are the only calls?"

"And you just missed an update from Mike. Scotty Taren's still waiting it out on Sixth Avenue. But they think Dr. Ichiko pulled a fast one, to avoid the police and save his best stuff for his television debut. He didn't show up for work today."

Mercer arrived in my office with Annika Jelt at one, to prepare for the afternoon grand jury. An attendant from the hospital accompanied the young student, who was brought to me in a wheelchair because of her still-fragile physical condition.

He sat beside her and held her hand as she went over all the details of her attack. Her English was excellent as she spoke softly but with determination. Annika described how her assailant had appeared quite suddenly, out of nowhere. Like the others before her, she had no idea whether she had been followed for any distance to the stoop of her building.

It took me the better part of an hour to get from Annika every nuance of the aborted assault, and then another fifteen minutes-once the afternoon grand jurors reconvened-to present her testimony to them. It was clear now that it was only the resistance she mounted at the top of the staircase-unwilling to give her assailant the opportunity to get her alone behind her closed apartment door-that led to the frenzied stabbing.

Mercer wheeled her back to my office to get her coat and turn her over to the attendant from the hospital.

"It's so wonderful to see how much stronger you are, how much you've improved, in just this short time. I know you've got a long way to go, Annika, but you've made a great start. Do you know when you're leaving for Sweden?" I asked.

"As soon as the doctors tell me it's safe for me to fly. The pressurized cabins are not good for my lungs yet, and the flight is so long. But you'll call me there if you catch the man, no?"

"The City of New York will buy you the ticket back here to testify and I'll be your personal escort," Mercer said.

"The posters-may I ask you a question about them?" Annika said. "One of the nurses showed me a poster."

Neighborhood groups had reproduced the composite sketch and circulated it to stores and businesses on the Upper East Side, urging them to hang it in their windows and behind their counters, in case the rapist made an appearance.

"What about it?"

"The poster has one of the drawings on it from the group Detective Wallace showed to me, the one I identified last week. It looks just like him-exactly like the man who did this to me. But what it says on the writing below the picture, well…"

"You don't have to be hesitant," I said. "If you noticed something different, you can tell us." Some people were more accurate at estimating height or weight. Some could remember the feel of facial hair rubbing against them that others hadn't even observed, or notice the smallest of scars or blemishes on the skin of a perpetrator.

"The drawing the detective showed me didn't have any writing on it. But the poster does."

Mercer and I both nodded.

"You know where it says the guy is African-American?" Annika asked.

Mercer seated himself on a chair opposite his witness and let her talk directly to him. "Yeah, you told me he was a black man."

"Of course, yes. But, maybe this is because I'm foreign, because English is a second language for me and I hear it differently."

I didn't know where she was going with this.

"The other women," she asked, "were any of them foreign-born?"

Mercer thought for a moment. "No."

"Well, I don't think the man is American. That's the word that troubles me. Black, yes. African-American, no."

"What then? Caribbean?"

"I can't say that. I haven't had much experience with people from the islands. It wasn't all-how you say?-singsong, like a few of the Jamaicans in my class at school. Not like that at all."

"Can you give me an example?" Mercer said. "He didn't speak very many words to you."

"No, no. It's-well, maybe it's not important then," Annika said, rolling the wheels of her chair backward and averting Mercer's glance, as though she feared wasting his time.