She was fifty years old, female, Hispanic of unspecified geographic origin, five-seven, one hundred and thirty-five pounds. She had joined the police force later in life than most cops-after the army, college, and a master’s degree in criminal justice. She’d even done two years of law school, but hadn’t finished. No one knew why she’d dropped out. What people did know was that she had shot up through the BPD ranks with incredible speed. The jealous credited affirmative action, ignoring the fact that she had the best clear rate in the homicide unit. In her fifteen years on the detective squad, she’d cleared over seventy-five percent of her cases. That meant that if a case was assigned to her, three out of four times someone was convicted of the crime. The national average was sixty-five percent. In Boston, the average had sunk in recent years as low as thirty-three percent. That meant that only a third of all murders were being solved. It was one of the worst records in the country. Given that grim reality, affirmative action or not, seventy-five percent made Sanchez a star.

Word was, though, that she was difficult to work with. Since joining the detective squad, she’d churned through five partners. Those inclined to give her the benefit of the doubt claimed that her intensity burned partners out. Those less charitable said it was because she couldn’t be trusted, and without trust there could be no real partnership. Whatever the reason, she was working alone when Stone was bumped up to homicide. He’d been told the arrangement was on a trial basis, but had been given no indication when the trial would end or by what criteria he would be judged. He was a team player, so he kept his mouth shut. At the very least, he figured, he could learn something riding with someone who had a seventy-five percent clear rate, no matter for how short a time.

“You got the address?” she asked.