It's 5:38 on a March morning when Alex's phone jars her awake. Homicide detective Mike Chapman is at the scene of a sexual assault and murder. It's a perfect case for Alex and her special skills.

And it's certain to be a high-profile case because the victim was a neurosurgeon at Mid-Manhattan Medical Center, the oldest and largest hospital in New York City. Dr. Gemma Dogen was found barely breathing, on the floor of her blood-soaked office. It was too late to save her. In cop parlance, she was a "likely to die.".

The problems Alex's team faces are immense, starting with too many possible suspects. Not only have Alex's colleagues prosecuted some of the hospital's employees and patients in the past - any one of them could be the killer - but the more than fifteen-hundred-bed complex and its medical college are connected to the Stuyvesant Psychiatric Center, and all three buildings sit on top of a maze of underground tunnels.

Scores of transients now populate the tunnels, putting on white coats or scrubs to enter and roam the hospital's corridors as if they were licensed professionals. Anybody could have been near Gemma Dogen's office the night of the murder.

While Alex and Mike and police colleague Mercer Wallace step up their search for the killer, Alex must also supervise other cases: the taxi driver who stalks an emergency room physician; a rapist who attacks a comatose young woman; a rabbi who demands a peculiar kind of service from his housekeepers.

But it is the Dogen case that disturbs Alex's dreams. The daughter of a cardiologist, Alex had always revered the medical profession. Now she begins to question her own biases. And what about the new man in her life? She met him at an elegant dinner party that is typical of her affluent Upper East Side lifestyle, but is he, too, somehow involved in this case?

Policewoman Maureen Forester may discover some of the shocking answers when she volunteers to check into the hospital as a decoy with a supposed neurological problem. With Alex and Mike temporarily far away, Maureen is more vulnerable than Alex could ever have imagined. And with the killer beginning to focus on Alex, she, herself, may soon bear the tragic label "likely to die."