But who?

- Four federal agents are waiting when the helicopter lands at a ranch farther down in Nayarit.

Adn looks at Nacho. "I guess you'll take Tijuana on your own. And the rest of it."

"Come on," Nacho says.

They get out of the helicopter and follow the agents into the house.

Four million dollars later, the helicopter takes off again, with Nacho Esparza, Diego Tapia, and Adn Barrera on board.

- Keller has a cup of coffee in a Condesa cafe, and then does a little shopping at El Pendulo bookstore. He picks up an Elmer Mendoza novel, then walks along Avenida Amsterdam, which used to be part of the old racetrack, and stops in at Parilladas Bariloche for a reasonably inexpensive dinner of papas con amor and arrachera. Sitting there perusing the Mendoza, he knows that he's the image of the lonely, middle-aged divorced man-reading alone at a table for one.

Maybe, Keller thinks, I've become too used to solitude.

Maybe I like it too much.

He finishes dinner and then walks over to the Parque Mexico.

Barrera has gone radio silent-no calls, no e-mails, no sightings, not even any rumors.

The trail is cold and dead.

The next meeting of the Barrera Coordinating Committee has the feel of a postmortem. Keller looks at his colleagues and wonders which, if either of them, has been tipping off Barrera.

He's also aware that he's been told to keep his big mouth shut about it-Mexican law enforcement has its shiny new soul-and Art Keller is not going to besmirch it. And the truth is that he doesn't have anything solid, just his suspicions.

And his gut feeling that both of these men are about to throw in the towel.

Aguilar is actually right when he points out to Keller that the search for Barrera is only one part of a multifaceted effort, and that neither SEIDO nor AFI can commit all their time and resources for what seems to be an increasingly quixotic quest.

Keller hears the subtext-we're going to get you the hell out of here-and he's too smart to hasten the process of his own demise by making noise about corruption.

"Let me tilt at one more windmill," he says.

- Keller and Vera watch from behind the one-way glass as Aguilar interviews Sondra Barrera.

She looks like hell, Keller thinks.

The Black Widow.

"You were present at the Christmas party in El Puente prison," Aguilar says.

"I don't know anything about that," Sondra answers.

"Well, you were there," Aguilar says. "We have witnesses."

Sondra doesn't respond.

"You were there with your son Salvador and other members of the family," Aguilar says.

"I don't know-"

"Where is Adn Barrera?"

Sondra laughs.

"Did I say something funny?" Aguilar asks.

"Do you think Adn would tell me where he is?" Sondra asks. "Do you think I would tell you if I knew?"

"Do you know?"

Sondra Barrera has no love for her brother-in-law, Keller knows, but she's not going to give him up, even if she could. He's her paycheck, her pension, her social security.

"My husband is dead," Sondra says.

"I'm aware of that," Aguilar answers. "What are you getting at?"

"That Adn has an instinct for survival," Sondra says. "Other people die for him. You'll never find him."

"Is he in touch with your son, Salvador?"

"Leave my son alone."

Keller sees the alarm in her eyes. Aguilar must have seen it, too, because he presses, "Tell me where Adn is and I won't have to speak to your son."

"He's good," Vera says to Keller. "Whatever else you can say about the persnickety bastard, you have to admit he's good."

"Please leave my son alone," Sondra says, on the verge of tears.

"I wish I could."

"You're bastards, all of you."

"You're hardly in a morally superior position, Seora Barrera," Aguilar says. "Do you know how many people your late husband killed?"

Sondra doesn't answer.

"Would you like to know? Does it matter to you? No, I thought not." He hands her his card. "This is my number. If Adn contacts you, I hope you will call me. And please have Salvador make an appointment. I don't want to pick him up on campus and embarrass him."

After Sondra and her lawyer leave, Aguilar comes into the room and sits with Keller and Vera. "Well, that was useful."

"It was," Keller says. "I know Sondra-she'll panic."

"Do we have a trace on her phones?" Vera asks.

"Of course," Aguilar answers. "And her son's."

"Luis is getting into the game," Vera says, getting up to leave.

"I've been in the game," Aguilar answers.

But Vera is already out the door.

Aguilar turns to Keller and says defensively, "I've been in the game."

- Sondra calls a number in Culiacn. "...they're talking about obstruction charges."

"They're bluffing."

"It's not Adn's voice," Keller says.

"No," Aguilar agrees.

"I will not go to prison. I will not have my son go to prison."

"Relax. We'll fix it."

"What does that mean?" Keller asks.

"I don't know," Aguilar snaps.

"Call him."

"That's not necessary. We can take care of it."

"He's not leaving us hanging out there."

"You know he wouldn't do that."

"I don't know that."

"Sondra-"

She hangs up.

"Who was she talking to?" Keller asks.

"Esparza?" Aguilar asks. "Tapia? I don't know."

But now they have the number she called, and it's a simple matter of technology to tap its calls.

They sit through a long night. Finally the man in Culiacn, now code-named "Fixer," makes a call to the 777 area code-Cuernavaca. "Sondra's panicking."

"Tell her to calm down."

"You don't think I did? She wants us to talk to him."

"To say what? Just fix it."

"Obviously. If she gives us the time."

"What can she tell them?"

"Who knows what she knows?"

"Silly bitch. What about the kid?"

"He's his father's son."

"The man loves him."

"Then we should tell him."

Keller feels a jolt shoot through his body. The men on the phone call are about to contact Adn.

The next minutes are agony.

Aguilar orders an underling, "Get Vera in here."

The AFI chief shows up twenty minutes later, disheveled, in a tracksuit and sweatshirt. "This had better be good. I've been seducing this woman for weeks."

Aguilar briefed him.

They sit in silence, watching the phone monitor.

Hoping, praying.

Then it lights up.

"Cuernavaca" is on the phone.

"Jesus," Vera says. "It's 555-a Mexico City number. Barrera's here."

Here, Keller thinks, in Mexico City. He's so goddamn smart, Barrera, he flies under the radar by getting under the radar's shell. You have to hand it to the son of a bitch, it's as clever as it is arrogant.

Classic Adn Barrera.

Keller listens as "Cuernevaca" says, "It's me."

"What is it?"

"Is that Barrera?" Aguilar asks.

"Can't tell," Keller answers.

They listen as "Cuernavaca" describes the problem with Sondra Barrera. Then the recipient of the call says, "The pendejos, why do they have to interfere with families?"