Slater heard them, but wondered if they were really prepared to stand by and let the girl die. Her father was screaming the few words of English he knew, “Help! U.S.A! Please, help!” He was on his knees in the dust, wringing his woven cap in his hands.

Her little heart was beating like a trip-hammer and her limbs were convulsing, and Slater knew that any further delay would seal the girl’s fate forever. Someone this size and weight, injected with a full dose of a pit viper’s poison — and he had seen enough of these snakes to know that this one had been fully mature — could not last long before her blood cells began to disintegrate.

“Keep her as still as you can,” he said to Groves and Diaz, then ran back to the jeep, grabbed the radio mike, and called it in to the main base.

“Marine down!” Slater said, “viper bite. Immediate — I say, immediate — evac needed!”

He saw Groves and the private exchange a glance.

“Your coordinates?” a voice on the radio crackled.

The coordinates? Slater, the blood pounding in his head from his own fever, fumbled to muster them. “We’re about two klicks from the Khan Neshin outpost,” he said, focusing as hard as he could, “just southwest of the rice paddies.”

Groves suddenly appeared at his side and grabbed the mike out of his hands, but instead of countermanding the major’s order, he gave the exact coordinates.

“Tell ’em they can finish the rations dump later,” Groves barked. “We need that chopper over here now! And tell the med center to get as much of the antivenin ready as they’ve got!”

Slater, his legs unsteady, crouched down in the shade of the jeep.

“You didn’t need to get mixed up in this,” Slater said after Groves signed off. “I’ll take the heat.”

“Don’t worry,” Groves said. “There’ll be plenty to go around.”

For the next half hour, Slater kept the girl as tranquilized as he could — the more she thrashed, the faster the poison circulated in her system — while the sergeant and the private kept a close watch on the neighboring fields. Taliban fighters were drawn to trouble like sharks to blood, and if they suspected a chopper was going to be flying in, they’d be scrambling through their stockpiles for one last Stinger missile. Nor did Slater want to go back to the outpost and ask for backup; somebody might see what was really going on and cancel the mission.

“I hear it!” Groves said, turning toward a low rise of scrubby hills.

So could Slater. The thrumming of its rotors preceded by only seconds the sight of the Black Hawk itself, soaring over the ridgeline. After doing a quick reconnaissance loop, the pilot put the chopper down a dozen yards from the jeep, its blades still spinning, its engine churning. The side hatch slid open, and two grunts with a stretcher leapt out into the cloud of dust.

“Where?” one shouted, wiping the whirling dirt from his goggles.

Diaz pointed to the girl lying low on the embankment between Slater and the sergeant.

The two soldiers stopped in their tracks, and over the loud rumble of the idling helicopter, one shouted, “A civilian?”

The other said, “Combat casualties only! Strict orders.”

“That’s right,” Slater said, tapping the major’s oak leaf cluster on his shirt, “and I’m giving them here! This girl is going to the med center, and she’s going now!”

The first soldier hesitated, still unsure, but the second one laid his end of the stretcher on the ground at her feet. “I’ve got a daughter back home,” he mumbled, as he wrapped the girl in a poncho liner, then helped Groves to lift her onto the canvas.

“I’m taking full responsibility,” Slater said. “Let’s move!”

But when the girl’s father tried to climb into the chopper, the pilot shook his head violently and waved his hand. “No can do!” he shouted. “We’re carrying too much weight already.”

Slater had to push the man away; there wasn’t time to explain. “Tell him what’s going on!” he shouted to the sergeant.

The father was screaming and crying — Diaz was trying to restrain him — as Slater slid the hatch shut and banged on the back of the pilot’s seat. “Okay, go, go, go!”

To evade possible fire, the chopper banked steeply to one side on takeoff, then zigzagged away from the rice paddies; these irrigated areas, called the green zone, were some of the deadliest terrain in Afghanistan, havens for snipers and insurgents. Slater heard a quick clattering on the bottom of the Black Hawk, a sound like typewriter keys clicking, and knew that at least one Taliban fighter had managed to get off a few rounds. The helicopter flew higher, soaring up and over the barren red hills, where the rusted carcasses of Soviet troop carriers could be seen half-buried in the dirt and sand. Now it would just be a race against time. The girl’s face was swollen up like she had the mumps, and Slater slipped the oxygen mask onto her as gently as he could. Her ears were like perfect little shells, he thought, as he looped the straps around the back of her head. She took no notice of what was being done, or where she was. She was delirious with the pain and the shock and the natural adrenaline that her body was instinctively pumping through her veins nonstop.

The soldiers stayed clear, strapped into their seats beside the ration pallets they’d been delivering and watching silently as Major Slater treated her. The one with the daughter looked like he was saying a prayer under his breath. But this little Afghan girl was Slater’s problem now, and they all knew it.

By the time the chopper cleared the med center perimeter and touched down, her eyes had shut, and when Slater lifted the lids, all he could see was the whites. Her limbs were pretty still, only occasionally rocked by sudden paroxysms as if jolts of electricity were shooting through her. Slater knew the signs weren’t good. It would have been different if he’d had the antivenin with him in the field, but it was costly stuff, in short supply, and it deteriorated rapidly if it wasn’t kept refrigerated.

Some of the staff at the med center looked surprised at the new admission — a local girl, when they’d been expecting a Marine — but Slater issued his orders with such conviction that not a second was lost. Covered with dirt and sweat, his fingers stained with snake blood, he was still clutching her limp hand as she was wheeled into the O.R., where the trauma team was ready with the IV lines.

“Careful when you insert those,” Slater warned. “The entry points are going to seep from the venom.”

“Major,” the surgeon said, calmly, “we know what we’re doing. We can take it from here.”

But when he tried to let go, the girl’s fingers feebly squeezed his own. Maybe she thought it was her dad.

“Hang in there, honey,” Slater said softly, though he doubted she could hear, or understand, him. “Don’t give up.” He extricated his fingers, and a nurse quickly brushed him aside so that she could get at the wound and sterilize the site. The surgeon took a syringe filled with the antivenin, held it up to the light, and expressed the air from the plunger.

Slater, knowing that he was simply in the way now, stepped outside and watched through the porthole in the swinging doors. The doctor and two nurses went through their paces with methodical precision and speed. But Slater was afraid that too much time had passed since the attack.

A shiver hit him, and he slumped into a crouch by the doors. This was the worst recurrence of the malaria he’d had in months, and the sudden blast of air-conditioning made him long for a blanket. But if he let on how bad it was, he could find himself restricted to desk duty in Washington — a fate he feared worse than death. He just needed to get back to his bunk, swallow some meds, and sweat it out for a day or two. The blood was beating in his temples like a drum.

And it got no better when he heard the voice of his commanding officer, Colonel Keener, bellowing from down the hall. “Did you call in this mission, Major Slater?”