At the time she had been living with Frank Hackett, another detective. They had been together eight years, although they had never married. When she fell out of favor, he left her. It still hurt.

Two young officers got out of the patrol car, a man and a woman. Toni knew most local police of her own generation, and some of the older ones remembered her late father, Sergeant Antonio Gallo, inevitably calledSpanish Tony. However, she did not recognize these two. Over the headset,she said, "Jonathan, the police have arrived. Would you please decontaminate and talk to them? Just say we have confirmed the escape of a virus from the lab. They'll call Jim Kincaid, and I'll brief him when he gets here."

Superintendent Kincaid was responsible for what they called CBRN-chemical, biological, radiological, and nuclear incidents. He had worked with Toni on her plan. The two of them would implement a careful, low-key response to this incident.

By the time Kincaid arrived, she would like to have some information to give him about Michael Ross. She went into the house. Michael had turned the second bedroom into his study. On a side table were three framed photographs of his mother: as a slim teenager in a tight sweater; as a happy parent, holding a baby that looked like Michael; and in her sixties, with a fat black-and-white cat in her lap.

Toni sat at his desk and read his e-mails, operating the computer keyboard clumsily with her rubber-gloved hands. He had ordered a book called Animal Ethics from Amazon. He had also inquired about university courses in moral philosophy. She checked his Internet browser, and found he had recently visited animal-rights Web sites. Clearly, he had become troubled about the morality of his work. But it seemed no one at Oxenford Medical had realized that he was unhappy.