"And abort the expedition two weeks earlier than the schedule calls for?"

"Schedule?" an American shouted. "Schedule? What the hell difference does the damned schedule make? We’re talking human lives here!"

The chief controller pressed both his hands together, almost as if praying. "I am afraid that your suggestion is the only reasonable course of action that we have open to us. Even though it is not entirely free of risk."

"It means that the people in the rover will have to wait at least another two days before the lander can be sent to them."

"I doubt that we can close down the operations at the dome and bring all those people up with their equipment and specimens in just two days. The schedule calls for a full week to shut down the dome."

"This is an emergency! Leave the equipment and specimens. Bring up the people and get on with the rescue, for god’s sake!"

"Leave everything?"

"Retrieve it on the next mission."

"There won’t be another mission. Not if we have to abandon this one, run away from Mars like thieves in the night."

"That’s the most stupid metaphor I’ve heard yet!"

"Just because you’re a woman doesn’t give you the right to…"

"Silence!" roared the chief controller. "I will not have us squabbling like children in a schoolyard. We will abort the mission. We will bring up the people in the dome as quickly as possible and then send the last of the landers to pick up the traverse team in the canyon. Anyone who wants to go on record as being against that decision should raise his or her hand. Now."

Not a single hand went up.

"And it is also agreed," the chief controller added, "that none of the expedition members will be allowed back to Earth unless and until this medical problem is solved. They will remain quarantined in Earth orbit."

"If they get that far," someone said in a stage whisper.

WASHINGTON: Edith could tell from Alberto’s face that something had gone very wrong.

"What is it?" she asked.

They were in the kitchen of the Georgetown house, just finishing breakfast before heading to Capitol Hill. Brumado had a date to testify before a congressional subcommittee holding hearings on the next fiscal year’s budget for space. The kitchen overlooked a lovely garden bounded by a red-brick wall. Most of the flowers were gone this late in the season, except for the hardy little impatiens lining the curved brick walkway with pink-and-white blooms that nodded in the soft morning breeze.

"What is it?" Edith asked again.

Brumado was at the telephone by the sink. His face was ashen. "My daughter… the traverse team… they are stranded in the canyon. Their rover vehicle has bogged down."

Edith got up from the glass-topped table, her breakfast instantly forgotten. "They have the backup rover, don’t they? They can pick them up…"

But Brumado was shaking his head. "They’re sick. All of them on the ground team. Something has made them all very sick and weak."

"Jamie too?"

"Yes. Him too."

Edith felt her own breath catch in her throat. She swallowed hard, then asked, "What’re they going to do?"

"NASA has offered to fly me to Houston, the mission control complex there."

"But what about Jamie and your daughter?"

"I must testify to the subcommittee," Brumado was muttering absently, like a man in shock. "They asked me not to reveal any of this. Not yet."

"But Jamie?"

Abruptly he seemed to realize she was standing in front of him. "Edith, I must have your word that you will not break this news to your network."

"Hey, I don’t have a network anymore. I’m unemployed, remember? But what about Jamie? Is he…"

"I don’t know!" Brumado snapped. Edith realized that he was fighting to maintain his self-control. She saw tears glimmering in the corners of his eyes.

"Maybe you ought to cancel the subcommittee appearance," she suggested.

"No," he said, more gently. "No, I can’t do that. It would raise suspicions."

"You could have a cold, for god’s sake."

"And then fly off to Houston?" He smiled without humor. "Half the subcommittee would be on the next plane. Or their aides, at least."

"Yeah, maybe," Edith admitted.

"Will you promise me not to call anyone, not to break the story?"

"Can I go to Houston with you?"

"Yes. Of course."

"Okay."

"You promise not to contact anyone about this while I am testifying this morning?"

"We have a deal, don’t we?"

But Edith was thinking, In Houston I can see how bad it really is, how tough a spot they’ve put Jamie into. An eyewitness account of Alberto Brumado watching as the team on Mars tries to rescue his daughter who’s stuck a thousand kilometers from their base. And sick. I could write my own ticket with that.

Sick from what? What’s happened to them? To Jamie?

Inwardly she made up her mind to keep her silence only until she was certain that they were doing everything they could for Jamie and the others. I’ve got to find out how they got into this mess. The minute I find out whose fault it is, then all deals are off.

This could be even bigger than finding life on Mars: four explorers trapped and sick a thousand kilometers from safety. That’s a real story! You don’t have to be a scientist to get excited about that.

Tony Reed smiled bitterly as the computer screen scrolled the list from the medical program’s analysis.

"Just as I told you," he said to Dr. Yang. "The idiot machine has nothing new to tell us."

Sitting beside him at the infirmary desk, Yang Meilin scanned the short list as a woman lost on the desert would search the horizon for an oasis.

"The answer is here," she said, barely loud enough for Reed to hear her. "I am certain of it."

The anger that Tony had felt earlier was gone now. Yang was not going to upstage him. She was just as bewildered and frustrated as he was. He felt almost sorry for her. Sorry for both of them. The two great medical experts, he said to himself, as stymied as a pair of chimpanzees. Says worlds for the selection board, doesn’t it?

"I have a feeling," Yang said, pressing one hand flat against her middle, "that we have seen the answer, but we do not yet recognize it."

Reed let a thin sigh escape. "Feelings are one thing," he said almost gently. "What we need are facts."

"The one clear fact that we have," she said, "is that everyone here on the ground is ill, except you."

Tony felt a pang of guilt. "Yes. That’s what’s so damned puzzling about all this, isn’t it?"

"What are you doing that the others are not?"

He shook his head. "Not a damned thing, as far as I can tell. I breathe the same air, I eat with them…"

"Something in the food?"

Leaning back in his chair, Tony replied, "I can’t imagine that there is something in my meals that is protecting me from whatever the others have come down with. Or conversely, that their food is tainted in some way and mine just happens not to be."

"Vitamin deficiency is on the computer’s list."

"Yes, I know." Some of the old exasperation was creeping back into Tony. "But we’ve checked that out time and again. They all take their vitamin supplements, just as I take mine. It can’t be that."

"You take the same pills they take?"

"Yes, of course."

"Every day?"

"Yes."

Yang lapsed into silence and turned her eyes back to the screen, as if she thought that by staring at it hard enough the answer would come clear.

Something nagged at Reed’s consciousness. Something peripheral, subliminal. As if they had touched on the answer without knowing it. As if…

It can’t be the vitamins, he told himself. I take the same dietary supplements that the others do every day. I watch them all swallow them down with their breakfasts every morning. The four in the rover are out of my sight, of course, but I check with them every day.