So that had been the beginning. Following Mr. Bob's recommendation, she switched from evenings to nights, which was easy, because the graveyard shift was the least popular. The benefit was that during the wee hours of the morning, there was less oversight, which made roaming the floors, checking the charts, and generally catching the gossip much easier than during the day or even during the evening. Mr. Bob had had other helpful recommendations as well, which he explained came from the fund of experience they'd had over several decades. He said that Jazz was joining an extensive, elite underground.

Jazz had flourished from the start. The clandestine nature of the operation was an added benefit; it even made going to work fun. The money was wired into an offshore account that had been set up for her by whoever "they" were. It grew rapidly, and it grew tax-free. The only problem was that in order to use the money, she had to go down to the Caribbean, a necessity that she found was hardly an imposition.

But then, after four years and several moves to different hospitals, the last being to St. Francis in Queens, things got even better. Mr. Bob reappeared to say that as a consequence of her outstanding work, she'd been commissioned along with a very select group to be raised in rank within the underground task force. She was now going to participate in an even more important mission, for which her compensation would be greatly increased. At the same time, so would the level of secrecy. It was a highly classified operation code-named "Operation Winnow."

Jazz remembered that he laughed after telling her the name. He said he had nothing to do with its selection, since it reminded him of "minnow." But his laughter quickly died off, and he again emphasized the secrecy. He said, "There are to be no ripples on the surface." He had asked if Jazz understood. Of course she understood.

Mr. Bob had gone on to explain that the circumstance would be the opposite of the setup with the "adverse outcomes," which she was to continue as well. With Operation Winnow, she would receive a patient's name by e-mail. Then, following a carefully devised protocol, which she had to follow to the letter, she would sanction the patient.

There had been a pause at that point. At first, Jazz didn't get his drift. She was confused by the word "sanction" until it finally dawned on her. When it did, it gave her a shiver of anticipation.

"This protocol has been masterminded by professionals, and it is completely foolproof," Mr. Bob had said. "There is no way it can be discovered, but you must follow it exactly as specified. Do you read me?"

"Of course I read you," Jazz had replied. What did he think she was, stupid?

"Are you interested in becoming part of the team?"

"That's affirmative," Jazz had said. "But you haven't told me the compensation."

"Five thousand a case."

Jazz could remember the smile that had appeared on her face. To think she would be paid five thousand dollars to do something challenging and fun was almost too good to be true. And it turned out to be better than she imagined. After the first five missions, which went off without a hitch, thanks to the protocol provided, Mr. Bob had appeared along with the Hummer.

"It's a token of our appreciation," he had explained while handing Jazz the keys and the papers. "Think of it as the antithesis of the pink Cadillac given out by that cosmetic company. Enjoy it in good health!"

Jazz exited the health club's parking garage onto Columbus Avenue. Stopping at the first red light, she activated her Blackberry.

From experience, she knew that reception was marginal inside the garage. She was rewarded with a message from Mr. Bob. With mounting excitement, she opened it. It was another name!

"Yes!" Jazz shouted with a grimace of determination like an athlete who had just executed a perfect move. Simultaneously, she punched the air with a fist. But then she quickly reigned in her response. Her military training immediately kicked in to bring her back to a proactive calmness. Getting another name after having gotten one the evening before suggested that she was about to begin another series. Although the names came in random intervals, they tended to be grouped together. She had no idea why.

Reaching over, Jazz put the Blackberry in the traylike indentation on the dash over the glove compartment. The motion caused her to hesitate when the light turned green. The taxicab to Jazz's right lurched forward with the intention of cutting into Jazz's lane to avoid a stopped taxi in his own lane. Jazz stomped on her accelerator to unleash the full power of the Hummer's V-8. The SUV shot forward and gobbled up the lead of the taxi in short order, forcing the driver to slam on his brakes. Jazz flipped him the finger as she shot by.

After several other close calls with taxis along Central Park South, Jazz worked her way over to the East Side and then north on Madison to the Manhattan General Hospital. It was ten-fifteen when she pulled into the complex's mammoth garage. One of the other benefits of working the graveyard shift was a plethora of parking spaces right near the garage's entrance into the hospital on the second floor. Collecting her Blackberry and slipping it into her left coat pocket, Jazz crossed the pedestrian bridge and went into the hospital.

As she had planned, she was a little early. She went directly to floor six, where she was assigned. It was a general surgical floor and always busy. After safely stashing her coat, she sat down at one of the computer terminals and casually typed in "Darlene Morgan." The evening ward secretary ignored her, busy wrapping things up so she could leave.

Jazz was pleased to learn that Darlene Morgan was in room 629 on Jazz's floor, which made the mission that much easier. She could always go to other floors on her breaks and lunch hour, which she had done on previous missions, but there was always the mild concern about arousing attention.

Leaving floor six, she took the elevator down to the first floor. There, she walked into the emergency room. As usual, it was pure pandemonium. Evening was its busiest time, and the waiting area was jammed with people and crying babies in all manner of illness and injury. It was the kind of chaos Jazz counted on. No one questioned when she walked into the storeroom where the parenteral or intravenous fluids were kept. Although she didn't expect any interference, even if she was seen, she still looked around to make sure she wasn't being observed. It was a reflex. When it was clear no one was watching her, she reached into the cardboard box containing the concentrated potassium chloride ampoules, took one out, and slipped it into her jacket pocket. As Mr. Bob had said, in the busy ER, it would never be missed.

With the first part of her mission accomplished, Jazz returned upstairs to wait for the nursing report and for her evening shift to begin. More out of curiosity than anything else, she pulled Darlene Morgan's chart to see if there was anything interesting or, for that matter, any explanation. Of course, she didn't care whether there was or wasn't.

Mommy, I want you to come home tonight," Stephen whined.

Darlene Morgan patted the top of her eight-year-old's head and exchanged a worried glance with her husband, Paul. Stephen was big for his age and at times could act reasonably mature, although that wasn't the case at present. He was genuinely nervous about his mother being in the hospital and wouldn't let go of her hand. Darlene had been surprised when Paul had showed up with the little guy in tow, since hospital rules dictated that visitors had to be twelve or older, and Stephen might have been big, but he didn't look twelve. But Paul had explained that Stephen pleaded to come to the point that Paul was willing to gamble that enforcement of the twelve-and-over rule would be minimal and that the floor nurses would turn a blind eye.