"Hey," called Mulder. They said nothing, only stared and shielded their eyes from the sun as the two grown-ups approached.

"Do you live around here?" asked Scully.

The boys exchanged looks. Finally one of them shrugged and said, "Yeah."

Mulder stopped and regarded them. Pretty standard-issue middle America boys in buzzcuts and T-shirts. Two of them straddled brand-new BMX bikes. "You see anybody digging around here?"

The boys remained silent, until one of them replied sullenly, "Not supposed to talk about it."

"You're not supposed to talk about it?" Scully prodded him gently. "Who told you that?"

The third boy piped up. "Nobody."

"Nobody, huh? The same Nobody who put this park in? All that nice new equipment…"

Mulder gestured at the swing sets, then looked sternly down into the boys' guilty faces. "They buy you those bikes, too?"

The boys shifted uncomfortably. "I think you better tell us," said Scully.

"We don't even know you," the first boy sniffed.

"Well, we're FBI agents."

The boy looked at Scully disdainfully. "You're not FBI agents."

Mulder suppressed a smile. "How do you know?"

"You look like door-to-door salesmen."

Mulder and Scully pulled out their badges. The boys' mouths dropped.

"They all left twenty minutes ago," one of the boys said quickly. "Going that way—"

They all pointed in the same direction.

"Thanks, guys," Mulder called. He pulled Scully after him and hurried toward the car.

The boys stood, silent, and watched as their rental car spun out onto the highway, red dust billowing behind it like smoke.

• • •

Mulder hunched at the wheel, foot to the floor. The car raced on, passing few other vehicles. Beside him Scully pored over the map, now and then looking out the window in concern.

"Unmarked tanker trucks…" Mulder said as to himself. "What are archaeologists hauling out in tanker trucks?"

"I don't know, Mulder."

"And where are they going with it?"

"That's the first question to answer, if we're going to find them."

They drove on, the sun moving slowly across the endless sky until it hung, a crimson disc, just above the horizon before them. It had been an hour since they'd seen another car. Mulder eased his foot from the accelerator, and let the car roll to stop. In front of them was an intersection. Each road seemed to go absolutely nowhere: Nowhere North or Nowhere South.

For several minutes the car sat idling. Finally Mulder spoke, rubbing his eyes.

"What are my choices?"

Scully blinked in the westerly light, then grimaced. "About a hundred miles of nothing in each direction."

"Where would they be going?"

Scully looked out her window, to where the asphalt road angled off and disappeared into the twilight.

"We've got two choices. One of them wrong."

Mulder stared out his window. "You think they went left?"

Scully shook her head, her gaze unmoving. "1 don't know why—I think they went right."

A few more minutes of silence passed. Then Mulder pounded his foot on the gas. The car arrowed straight ahead, onto the unpaved dirt road. They bumped over rocks and gullies, dust flaring up all around them as Mulder drove, his expression unrelentingly deter-mined. Scully stared at him, waiting for an explanation, but he refused to meet her gaze.

Ahead of them the sun disappeared. Red and black clouds streaked the darkening sky, and a few stars pricked into view. Scully rolled down her window and breathed in the night: mesquite, sage, dust.

Twenty minutes had passed, when Mulder turned to her and finally spoke.

"Five years together," he said in a tone that brooked no arguing. "How many times have I been wrong?"

A few quiet seconds pass. "At least not about driving."

Scully stared out at the night, and said nothing.

Hours went by. Mulder drove quickly, the silence unbroken save by the occasional wail of a dog or coyote, the shrieking of an owl. Outside the night sky glittered, nothing but stars as far as you could see, nothing at all. When the car began to slow Scully felt as though she were being awakened from a dream, and turned reluctantly from her window to gaze at what was before them.

Clouds of dust rose and settled in the vel' vety darkness. A few feet in front of the car, a line of fence posts stretched endlessly to the left and right, looped together by heavy strands of rusted barbed wire.

Wild white roses choked the fence with briars, and prickly pear cacti were clumped everywhere. There was no gate, and as far as Scully could see, no break in the fence.

She opened the door and got out. After the car's air-conditioning, the hot Texas wind was like standing in front of a wood stove. In the distance a dog barked. Scully walked to where the headlights washed over the fence, and stared at a sign nailed to a post. Behind her, Mulder's door opened, and he stepped out to join her.

"Hey, I was right about the bomb, wasn't I?" he asked plaintively.

"This is great," said Scully. "This is fitting."

She cocked her thumb at the sign.

SOME HAVE TRIED, SOME HAVE DIED. TURN BACK—NO TRESPASSING

"What?" demanded Mulder.

"I've got to be in Washington, D.C. in eleven hours for a hearing—the outcome of which might possibly affect one of the biggest decisions of my life. And here I am standing out in the middle of Nowhere, Texas, chasing phantom tanker trudis."

"We're not chasing trucks," Mulder said hotly, "we're chasing evidence."

" Of what, exactly?"

"That bomb in Dallas was allowed to go off, to hide bodies infected with a virus. A virus you detected yourself, Scully."

"They haul gas in tanker trucks, they haul oil in tanker trucks—they don't haul viruses in tanker trucks."

Mulder stared obstinately into the dark-ness. "Yeah, well, they may in this one."

"What do you mean by that?" For the first time Scully stared directly at him, her face clouded with anger and a growing suspicion. "What are you not telling me here?"

"This virus-" He turned away from her, afraid to go on.

" Mulder—"

"It may be extraterrestrial."

A moment while Scully gazed at him in disbelief. Then, "I don't believe this!" she exploded. "You know, I've been here—I've been here one too many times with you, Mulder."

He kicked at a stone and looked at her, all innocence. "Been where?"

"Pounding down some dirt road in the mid-dle of the night! Chasing some elusive truth on a dim hope, only to find myself right where I am right now, at another dead end—"

Her voice was abruptly cut off by the clang-ing of a bell. Blinding light strobed across their faces.

Stunned, they whirled to stare at the barbed-wire fence.

In the sudden burst of light, a railroad crossing sign appeared to hang in the empty air. No swinging metal arms or gate, just that sign, an eerie warning in the wilderness. Mulder and Scully stared at it open-mouthed, then turned to gaze at a light burgeoning upon the horizon. As they watched, it grew larger and larger, until it resolved into the headlamp of a train speed-ing toward them.

Wordlessly they backed to their car, but stopped as the train rushed past. And saw then what they had been chasing through the waste-land: two unmarked white tanker trucks, loaded piggyback on the flatbed cars. In seconds it was gone, swallowed by the night. The railroad crossing sign faded into the darkness, and silence once again overtook the prairie.