Slim and with a retiring demeanor, NYPD Detective Mel Cooper was a renowned forensic lab man. Rhyme would bully anybody, all the way up to and including the mayor, to get Cooper assigned to him, especially for a case like this, in which toxin seemed to be the murder weapon of choice. With degrees in math, physics and organic chemistry, Cooper was perfect for the investigation.

The CS tech cop nodded greetings to Eagleston and her partner, who like him were based in the massive NYPD crime scene oper-ation in Queens. Despite the ornery weather and a chill in the parlor, Cooper wore a short-sleeved white shirt along with baggy black slacks, giving him the appearance of a crusading Mormon elder or high school science professor. His shoes were Hush Puppies. People usually weren’t surprised to learn that he lived with his mother; the astonishment came when they met his towering and beautiful Scandinavian girlfriend, a professor at Columbia. The two were champion ballroom dancers.

Cooper, in a lab coat, latex gloves, goggles and mask, gestured to an empty evidence examination table. His colleagues set the cartons on it and nodded goodbye, then went out once more into the storm.

‘You too, rookie. Let’s see what we’ve got.’

Ron Pulaski pulled on similar protective gear and stepped up to the table to help.

‘Careful,’ Rhyme said unnecessarily, since Pulaski had done this a hundred times and no one was more careful than he with evidence.

But the criminalist was distracted; his thoughts returned to Amelia Sachs. Why wasn’t she calling? He remembered seeing the powder pour into the video camera lens at the same time it hit her face. Remembered her choking.

And then: a key in the door.

A moment later. Wind. A cough. A throat clearing.

‘Well?’ Rhyme called.

Amelia Sachs turned the corner of the parlor, pulling her jacket off. A pause. More coughing.

‘Well?’ he repeated. ‘Are you all right?’

Her response was to guzzle a bottle of water that Thom handed to her.

‘Thanks,’ she said to the young man. Then to Rhyme: ‘Fine,’ her low sultry voice lower and sultrier than normal. ‘More or less.’

Rhyme had known that she hadn’t been poisoned. He’d spoken to the EMT who specialized in toxins as she’d been shepherded to Manhattan General Medical Center. Her symptoms were atypical for poisoning, the med tech had reported, and by the time the ambulance got to Emergency, her only symptoms were a racking cough and teary eyes, which had been flushed several times with water. The unsub had created a less-than-lethal trap – but the irritant might have blinded her or played havoc with the lungs.

‘What was it, Sachs?’

She now explained that swabs of mucous membranes and a lightning-fast blood workup had revealed that the ‘poison’ was dust composed mostly of ferric oxide.

‘Rust.’

‘That’s what they said.’