"I don't expect you to say anything critical," María said. "You work with him. But I wanted you to now what that was about back there because you'll be working with me, too. I only learned he was here when I learned you would be coming with me. It was a difficult thing to accept, seeing him again."

"I understand," Aideen said. She practically had to shout to be heard over the roar of the rotor.

María showed her a little half-smile. "Luis tells me you worked to bring in drug dealers in Mexico. That took courage."

"To tell you the truth," Aideen said, "what it took was indignation, not courage."

"You are too modest," María shot back.

Aideen shook her head. "I'm being truthful. Drugs helped to wreck my neighborhood when I was a kid. Cocaine killed one of my best friends. Heroin took my cousin Sam, who was a brilliant organist at our church. He died in the street. When I got some experience under my belt, I wanted to do more than wring my hands and complain about it."

"I felt the same way about crime," she said. "My father owned a cinema in Madrid. He was killed in a robbery. But both of our desires would have been nothing if they weren't backed by courage and resolve. And cunning," she added. "You either have that or you acquire it. But you need it."

"I'll go along with resolve and cunning," Aideen said, "and one thing more. You have to learn to stifle your gag reflex in order to learn."

"I don't understand."

"You have to close down your emotions," Aideen explained. "That's what allowed me to walk the streets undercover-to observe dispassionately and to learn. Otherwise, you'd spend all your time hating. You have to pretend not to care as you talk to hawkers, learn the names of the 'houses" they represent. In Mexico City there were the Clouds, who sold marijuana. The Pirates, who sold cocaine. The Angels, who sold crack. The Jaguars, who sold heroin. You have to learn the difference between the users and the junkies."

"The junkies are always the loners, no?"

Aideen nodded.

"It's the same everywhere," María said.

"And the users always travel in packs. You had to learn to recognize the dealers in case they didn't open their mouths. You had to know who to follow back to the kingpins. The dealers were the ones with their sleeves rolled up-that was where they carried the money. Their pockets were for guns or knives. But I was always scared in the field, María. I was scared for my life and scared of what I would learn about the underbelly of someone else's life. If I hadn't been angry about my old neighborhood, if I weren't sick for the families of the lost souls I encountered, I could never have gone through with it."