In front of her, through the greasy windows, she could see the dilapidated streets of Gravesend fade into smoke and darkness. It seemed so large and impenetrable.

She wanted Tobe Geller here, she wanted the Georgetown psychologist, she wanted the list of on-line subscribers… Everything was taking too long! And there were far too few leads! Her hand balled into a fist, a nail pushing into her palm.

"Miss?" came the voice behind her. "Miss Agent? Here."

She turned. The anger dissipating like steam. The counterman was offering her a Styrofoam cup of coffee. In his other hand were two packets of sugar, a little plastic container of half-and-half and a stirrer.

The man had brushed his hair back with his hands and looked at her with a forlorn puppy gaze. He said simply, "It's getting colder out."

Touched by his oblique admiration, she smiled, took the cup and poured in one sugar.

"Hope you get some celebrating in tonight," he said.

"You too," she said. And pushed out of the door.

Walking down the cold streets of Gravesend.

She sipped the bad coffee, felt the hot steam waft around her mouth. It was getting colder.

Well, keep going, she thought. Get colder and colder. Today had been far too like autumn for her. Please… Snow like mad.

Scanning the street. The two agents from the field office were out of sight, probably on an adjacent block. Cage too had vanished. And Kincaid was still gazing into the store near the staging area.

Kincaid…

And what exactly was his story. Turning down a special-agent-in-charge slot? Lukas couldn't understand that-an SAC was the next destination on her roadmap to the dep director spot. And beyond. Still, even though she didn't comprehend his not wanting the position she respected him more for saying no than if he'd taken the job without wanting it.

What did explain the walls he'd put up around his life? She couldn't guess but she saw them clearly; Margaret Lukas knew walls. He reminded her of herself-or rather of her selves, plural. Jackie and Margaret both. Thinking of the changeling story she'd read years ago, she wondered what kind of books Parker read to his children. Dr. Seuss, of course-because of his nickname for them. And probably Pooh. And all the Disney spin-offs. She pictured him in that cozy suburban house-a house very similar to the one Jackie had lived in-sitting in the living room, a fire burning in the fireplace, reading to them as they lay sprawled at his side.

Lukas's eyes happened to fall on a young Latino couple walking down the sidewalk toward the staging area. The wife bundled in a black scarf, the husband in a thin jacket with a Texaco logo on the chest. He pushed a baby carriage, inside of which Lukas caught sight of a tiny infant, packed in swaddling, only its happy face visible. She thought instinctively about what kind of flannel she'd buy to sew the child a pair of pajamas.

Then the couple moved on.

Okay, Parker, you like puzzles, do you?

Well, here's one for you. The riddle of the wife and the mother.

How can you be a wife without a husband? How can you be a mother without a child?

It's a tricky one. But you're smart, you're arrogant, you're the third hawk. You can figure it out, Parker.

Lukas, alone on the nearly deserted street, leaned against a lamppost, curled her arm around it-her right arm, ignoring her own orders to keep shooting hands free. She gripped the metal hard, she gripped it desperately Struggled to keep from sobbing.

A wife without a husband, a mother without a child…

Give up, Parker?

I'm the answer to the riddle. Because I'm the wife of a man lying in the cold ground in Alexandria Cemetery. Because I'm the mother of a child lying beside him.

The riddle of the wife and mother…

Here's another: How can ice burn?

When an airplane drops from the sky into a field on a dark November morning, two days before Thanksgiving, six days before your birthday, a hot autumn day, and explodes into a million fragile bits of metal and plastic and rubber.

And flesh.

That's how ice can burn.

And that's how I became a changeling.

Oh, puzzles are easy when you know the answer, Parker.

So simple, so simple…

Hold on, she thought, letting go of the lamppost. Taking a deep breath. Locking away the urge to cry. Enough of that.

One thing Special Agent Lukas didn't tolerate was distraction. She had two rules she repeated endlessly to new recruits in the field office. The first was "You can never have too many deets." The second was "Focus."

And "focus" was what she now ordered herself to do.

Another breath. She looked around. Saw some motion in a vacant lot nearby-a young kid, wearing gang colors. He stood over an oil drum, waiting for some of his homeys. He had a teenagers attitude-which was a hell of a lot more dangerous than a thirty-year-old's, she knew. He gave her the eyeball.

Then up the street, a block away, she thought she saw a man in the alcove of a check-cashing store. She squinted. Was anybody there? Somebody hiding in the shadows?

No, there was no more motion. It must've been her imagination. Well, this's the place to get spooked.

Gravesend…

She tossed out the remains of the coffee and walked toward the teenager in the vacant lot to see if he knew anything about their mysterious unsub. Pulling the computer printout from her pocket, she wove easily around rusting auto parts and piles of trash-the same way Jackie Lukas used to maneuver through the perfume counters at Macy's on her way to a drop-dead sale in women's sportswear.

Parker stepped away from the thrift store, disappointed.

The stationery he'd seen inside wasn't the same as the extortion note or the envelope. He looked around the streets. He was shivering hard. He thought: Stephie's outgrown her down jacket. I'll have to get her a new one. And what about Robby? He had the fiberfill, the red one, but maybe Parker would get the boy a leather bomber jacket. He liked his fathers.

He shivered again and rocked on his feet.

Where the hell was that van? They needed the on-line service subscriber list. And the demolition and construction permit information. And the shrink. He wondered too what the tape of the shooting would show.

Parker looked around once more at the devastated streets. No Lukas, no Cage. He watched a young couple-they looked Hispanic-wheeling a baby carriage toward him. They were about thirty feet away. He thought about the times just after Robby was born when he and Joan would take after-dinner strolls like that.

Again his eye caught the man huddling in the check-cashing alcove. Absently wondered why he was still there. He decided to be useful and fished in his pocket for a picture of the unsub. He'd do some canvassing himself.

But something odd was happening…

The man looked up and, though Parker couldn't see clearly through the dim light and smoke from the oil drums, reached into his coat and pulled something out, something black, shiny.

Parker froze. It was the man who'd followed them near the Archives!

It was the Digger!

Parker reached into his pocket, for the gun.

But the gun wasn't there.

He remembered the pistol pressing into his hip as he sat in Cage's car and he'd adjusted it in his pocket. It must have fallen out into the front seat.

The man glanced at the couple, who were between him and Parker, and lifted what must have been the silenced Uzi.

"Get down!" Parker cried to the couple, who stopped walking and stared at him uncertainly "Down!"

The Digger turned toward him and lifted the gun. Parker tried to leap into the shadows of an alley. But he tripped over a pile of trash and fell heavily to the ground. His breath was knocked out of him and he lay on his side, gasping, unable to move, as the man walked steadily closer. Parker called to the couple once more but his voice came out as a breathy gasp.