Doc Feldman's luck was better than he had expected. For an Earth year, he was a doctor again, moving about from village to village as he was needed and doing what he could.

The village had been isolated during the early colonization when Mars made a feeble attempt to break free of Space Lobby. Their supplies had been cut off and they had been forced to do for themselves. Now they were largely self-sufficient. They grew native plants and extracted hormones in crude little chemical plants. The hormones were traded to the big chemical plants for a pittance to buy what had to come from Earth. Other jury-rigged affairs synthesized much of their food. But mostly they learned to get along on what Mars provided.

Doc Feldman learned from them. Money was no longer part of his life. He ate with whatever family needed him and slipped into the life around him.

He was learning Martian medicine and finding that his Earth courses were mostly useless. No wonder the villagers distrusted Lobby doctors. Doc had his own little laboratory where he had managed to start making Mars-normal penicillin—a primitive antibiotic, but better than nothing.

Jake had come to remind him that it was his first anniversary, and now they were smoking bracky together.

"Sheer luck, Jake," Doc repeated. "You Martians are tough. But some day someone is going to die under my care, with the little equipment I have. Then—"

Jake nodded slowly. "Maybe, Doc. And maybe some day Mars will break free of the Lobbies. You'd better pray for that."

"I've been—" Doc stopped, realizing what he'd started to say. The old man chuckled.

"You've been talking rebellion for months, Doc. I hear rumors. Whenever you get mad, you want us to secede. But you don't really mean it yet. You can't picture any government but the one you're used to."

Doc grinned. Jake had a point, but it was not as strong as it would have been a few months before. The towns under the Lobby were cheap imitations of Earth, but here, divorced to a large extent from the lobbies, the villages were making Mars their own. Their ways might be strange; but they worked.

Jake shifted his body in the weak sunlight. "Newton village forgot to report a death on time. I hear Ryan is sweating them out, trying to prove it was your fault."

There was no evidence against him yet, Doc was sure. But Chris was out to prove something, and to get a reputation as a top-flight administrator. It must have hurt when they shipped her here as head of the lesser hemisphere of Mars. She'd expected to use Feldman as a front while she became the actual ruler of the whole Lobby. Now she wanted to strike back.

"She's using blackmail," he said, and some of his old bitterness was in his voice. "Anyone taking treatment from an herb doctor in this section is cut off from Medical Lobby service. Damn it, Jake, that could mean letting people die!"

"Yeah." Jake sighed softly. "It could mean letting people begin to think about getting rid of the Lobby, too. Well, I gotta help harvest the bracky. Take it easy on operating for a while, will you, Doc?"

"All right, Jake. But stop keeping the serious cases a secret. Two men died last month because you wouldn't call me for surgery. I've broken all my oaths already. It doesn't matter anymore."

"It matters, boy. We've been lucky, but some day one case will go to the hospital and they'll find your former work. Then they'll really be after you. The less you do the better."

Doc watched Jake slump off, then turned down into the little root cellar and back toward the room concealed behind it, where his crude laboratory lay. For the moment, he was free to work on the mystery of the black spots.

He kept running into them—always on the body of someone who died of something that seemed like a normal disease. Without a microscope, he was almost helpless, but he had taken specimens and tried to culture them. Some of his cultures had grown, though they might be nothing but unknown Martian fungi or bacteria. Mars was dry and almost devoid of air, but plants and a few smaller insects had survived and adapted. It wasn't by any means lifeless.

Without a microscope, he could do little but depend on his files of cases. But today there was new evidence. A villager had filched an Earth Medical Journal from the tractor driven by Chris Ryan and forwarded it to him. He found the black specks mentioned in a single paragraph, under skin diseases. Investigation of the diet was being made, since all cases were among people eating synthetics.

There was another article on aberrant cases—a few strange little misbehaviors in classical syndromes. He studied that, wondering. It had to be the same thing. Diet didn't account for the fact that the specks appeared only when the patient was near death.

Nor did it account for the hard lump at the base of the neck which he found in every case he could check. That might be coincidence, but he doubted it.

Whatever it was, it aggravated any other disease the patient had and made seemingly simple diseases turn out to be completely and rapidly fatal. Once syphilis had been called "The Great Imitator". This gave promise of being worse.

He shook his head, cursing his lack of equipment. Each month more people were dying with these specks—and he was helpless.

The concealed door broke open suddenly and a boy thrust his head in. "Doc, there's a man here from Einstein. Says his wife's dying."

The man was already coming into the room.

"She's powerful sick, Doc. Had a bellyache, fever, began throwing up. Pains under her belly, like she's had before. But this time it's awful."

Doc shot a few questions at him, frowning at what he heard. Then he began packing the few things that might help. There should be no appendicitis on Mars. The bugs responsible for that shouldn't have adapted to Mars-normal. But more and more infections found ways to cross the border. Gangrene had been able to get by without change, it seemed. So far, none of the contagious infections except polio and the common cold had made the jump.

This sounded like an advanced case, perhaps already involving peritonitis.

So far, he'd been lucky with penicillin, but each time he used it with grave doubts of its action on the Mars-adapted patients. If the appendix had burst, however, it was the only possible treatment.

He riffled through his stores; There was ether enough, fortunately. The villagers had made that for him out of Martian plants, using their complicated fermentation processes. He yelled for Jake, and the boy brought the old man back a moment later.

"Jake, I'll need more of that narcotic stuff. I don't want the woman writhing and tearing her stitches after the ether wears off."

"Can't get it, Doc." Jake's eyes seemed to cloud as he said it. "Distilling plant broke down. Doc, I don't like this case. That woman's been to the hospital three times. I hear she just got out recently. This might be a plant, or they figure they can't help her."

"They're afraid to try anything on Mars-normal flesh. They can't be proved wrong if they do nothing." Doc finished packing his bag and got ready to go out. "Jake, either I'm a doctor or I'm not. I can't worry when a woman may be dying."

For a second, Jake's expression was stubborn. Then the little crow's feet around his eyes deepened and the dry chuckle was back in his voice. "Right, Dr. Feldman." He flipped up his thumb and went off at a shuffling run toward the tractor. Lou and the man from Einstein followed Doc into the machine.

It was a silent ride, except for Doc's questions about the sick woman. Her husband, George Lynn, was evasive and probably ignorant. He admitted that Harriet had been to the dispensary and small infirmary that Southport called a hospital.

It was the only place in the entire Southern hemisphere where an operation could be performed legally. Most cases had to go to Northport, but Chris had been trying to expand. Apparently, she was determined to make Southport into another major center before she was called back to Earth.

Doc wondered why the villagers went there. They had no medical insurance with the Lobby; they couldn't afford it. Most villagers didn't have the cash, either. They were forced to mortgage their future work and that of their families to the drug plants that were run by the Lobby.

"And they just turned your wife away?" Doc asked. He couldn't quite believe that of Chris.

"Well, I dunno. She wouldn't talk much. Twice she went and they gave her something. Cost every cent I could borrow. Then this last time, they kept her a couple days before they let me come and get her. But now she's a lot worse."

Jake spun about, suddenly tense. "How'd you pay them last time, George?"

"Why, they didn't ask. I told her she could put up six months from me and the kids, but nobody said nothing about it. Just gave her back to me." He frowned slowly, his dull voice uncertain. "They told me they'd done all they could, not to bring her back. That's why she was so strong on getting Doc."

"I don't like it," Jake said flatly. "It stinks. They always charge. George, did they suggest she get in touch with Doc here?"

"Maybe they did, maybe not. Harriet did all the talking with them. I just do what she tells me, and she said to get Doc."

Jake swore. "It smells like a trap. Are you sure she's sick, George?"

"I felt her head and she sure had a fever." George Lynn was torn between his loyalties. "You know me, Doc. You fixed me up that time I had the red pip. I wouldn't pull nothing on you."

Doc had a feeling that Jake was probably right, but he vetoed the suggestion that they stop to look for spies. He had no time for that. If the woman was really sick, he had to get to her at once, and even that might be too late.

He remembered the woman, sickly from other treatment. He'd been forced to remove her inflamed tonsils a few months before. She'd whined and complained because he couldn't spend all his time attending her. She was a nag, a shrew, and a totally selfish woman. But that was her husband's worry, not his.

He dashed into the little house when they reached Einstein, and his first glance confirmed what George Lynn had said. The woman was sick, all right. She was running a high fever. Much too high.

She began whining and protesting at his having taken so long, but the pain soon forced her to stop.

"There may still be a chance," Doc told her husband brusquely. He threw the cleanest sheet onto a table and shoved it under the single light. "Keep out of the way—in the other room, if you can all pile in there. This isn't exactly aseptic, anyhow. You can boil a lot of water, if you want to help."

It would give them something to do and he could use the water to clean up. There was no time to wait for it, however. He had to sterilize with alcohol and carbolic acid, and hope. He bent over the woman, ripping her thin gown across to make room for the operation.

Then he swore.

Across her abdomen was the unhealed wound of a previous operation. They'd worked on her at Southport. They must have removed the appendix and then been shocked by the signs of infection. They weren't supposed to release a sick patient, but there was an easy out for them; they could remove her from the danger of spreading an unknown infection. Some doctors must have doped her up on sedatives and painkillers and sent her home, knowing that she would call him. For that matter, they might have noticed her unrecorded tonsillectomy and considered her fair bait.

He grabbed the ether and slapped a cone over her nose. She tried to protest; she never cooperated in anything. But the fumes of the ether he dipped onto the packing of the cone soon overcame that.

It was peritonitis, of course. The only thing to do was to go in and scrape and clean as best he could. It was a rotten job to have to do, and he should have had help. But he gritted his teeth and began. He couldn't trust anyone else to hold the instruments, even.

He cleaned the infection as best he could, knowing there was almost no chance. He used all the penicillin he dared. Then he began sewing up the incision. It was all he could do, except for dressing the wound with a sterile bandage. He reached for one, and stopped.

While he'd been working, the woman had died, far more quietly than she had ever lived.

It was probably the only gracious act of her life. But it was damning to Doc. They couldn't hide her death, and any investigation would show that someone had worked on her. To the Lobby, he would be the one who had murdered her.

Jake was waiting in the tractor. He took one look at Doc's face and made no inquiries.

They were more than a mile away when Jake pointed back. Small in the distance, but distinct against the sands, a gray Medical Corps tractor was coming. Either they'd had a spy in the village or they'd guessed the rate of her infection very closely. They must have hoped to catch Doc in the act, and they'd barely missed.

It wouldn't matter. Their pictures and what testimony they could force from the village should be enough to hang Doc.