Red Doctor Dal Timgar knew at once that there would be no problem in diagnosis here. The Black Doctor slumped back in his seat, gasping for air, his face twisted in pain as he labored just to keep on breathing. Tiger and Jack burst into the room, and Dal could tell that they knew instantly what had happened.

"Coronary," Jack said grimly.

Dal nodded. "The question is, just how bad."

"Get the cardiograph in here. We'll soon see."

But the electrocardiograph was not needed to diagnose the nature of the trouble. All three doctors had seen the picture often enough—the sudden, massive blockage of circulation to the heart that was so common to creatures with central circulatory pumps, the sort of catastrophic accident which could cause irreparable crippling or sudden death within a matter of minutes.

Tiger injected some medicine to ease the pain, and started oxygen to help the labored breathing, but the old man's color did not improve. He was too weak to talk; he just lay helplessly gasping for air as they lifted him up onto a bed. Then Jack took an electrocardiograph tracing and shook his head.

"We'd better get word back to Hospital Earth, and fast," he said quietly. "He just waited a little too long for that cardiac transplant, that's all. This is a bad one. Tell them we need a surgeon out here just as fast as they can move, or the Black Service is going to have a dead physician on its hands."

There was a sound across the room, and the Black Doctor motioned feebly to Tiger. "The cardiogram," he gasped. "Let me see it."

"There's nothing for you to see," Tiger said. "You mustn't do anything to excite yourself."

"Let me see it." Dr. Tanner took the thin strip of paper and ran it quickly through his fingers. Then he dropped it on the bed and lay his head back hopelessly. "Too late," he said, so softly they could hardly hear him. "Too late for help now."

Tiger checked his blood pressure and listened to his heart. "It will only take a few hours to get help," he said. "You rest and sleep now. There's plenty of time."

He joined Dal and Jack in the corridor. "I'm afraid he's right, this time," he said. "The damage is severe, and he hasn't the strength to hold out very long. He might last long enough for a surgeon and operating team to get here, but I doubt it. We'd better get the word off."

A few moments later he put the earphones aside. "It'll take six hours for the nearest help to get here," he said. "Maybe five and a half if they really crowd it. But when they get a look at that cardiogram on the screen they'll just throw up their hands. He's got to have a transplant, nothing less, and even if we can keep him alive until a surgical team gets here the odds are a thousand to one against his surviving the surgery."

"Well, he's been asking for it," Jack said. "They've been trying to get him into the hospital for a cardiac transplant for years. Everybody's known that one of those towering rages would get him sooner or later."

"Maybe he'll hold on better than we think," Dal said. "Let's watch and wait."

But the Black Doctor was not doing well. Moment by moment he grew weaker, laboring harder for air as his blood pressure crept slowly down. Half an hour later the pain returned; Tiger took another tracing while Dal checked his venous pressure and shock level.

As he finished, Dal felt the Black Doctor's eyes on him. "It's going to be all right," he said. "There'll be time for help to come."

Feebly the Black Doctor shook his head. "No time," he said. "Can't wait that long." Dal could see the fear in the old man's eyes. His lips began to move again as though there were something more he wanted to say; but then his face hardened, and he turned his head away helplessly.

Dal walked around the bed and looked down at the tracing, comparing it with the first one that was taken. "What do you think, Tiger?"

"It's no good. He'll never make it for five more hours."

"What about right now?"

Tiger shook his head. "It's a terrible surgical risk."

"But every minute of waiting makes it worse, right?"

"That's right."

"Then I think we'll stop waiting," Dal said. "We have a prosthetic heart in condition for use, don't we?"

"Of course."

"Good. Get it ready now." It seemed as though someone else were talking. "You'll have to be first assistant, Tiger. We'll get him onto the heart-lung machine, and if we don't have help available by then, we'll have to try to complete the transplant. Jack, you'll give anaesthesia, and it will be a tricky job. Try to use local blocks as much as you can, and have the heart-lung machine ready well in advance. We'll only have a few seconds to make the shift. Now let's get moving."

Tiger stared at him. "Are you sure that you want to do this?"

"I never wanted anything less in my life," Dal said fervently. "But do you think he can survive until a Hospital Ship arrives?"

"No."

"Then it seems to me that I don't have any choice. You two don't need to worry. This is a surgical problem now, and I'll take full responsibility."

The Black Doctor was watching him, and Dal knew he had heard the conversation. Now the old man lay helplessly as they moved about getting the surgical room into preparation. Jack prepared the anaesthetics, checked and rechecked the complex heart-lung machine which could artificially support circulation and respiration at the time that the damaged heart was separated from its great vessels. The transplant prosthetic heart had been grown in the laboratories on Hospital Earth from embryonic tissue; Tiger removed it from the frozen specimen locker and brought it to normal body temperature in the special warm saline bath designed for the purpose.

Throughout the preparations the Black Doctor lay watching, still conscious enough to recognize what was going on, attempting from time to time to shake his head in protest but not quite succeeding. Finally Dal came to the bedside. "Don't be afraid," he said gently to the old man. "It isn't safe to try to delay until the ship from Hospital Earth can get here. Every minute we wait is counting against you. I think I can manage the transplant if I start now. I know you don't like it, but I am the Red Doctor in authority on this ship. If I have to order you, I will."

The Black Doctor lay silent for a moment, staring at Dal. Then the fear seemed to fade from his face, and the anger disappeared. With a great effort he moved his head to nod. "All right, son," he said softly. "Do the best you know how."

Dal knew from the moment he made the decision to go ahead that the thing he was undertaking was all but hopeless.

There was little or no talk as the three doctors worked at the operating table. The overhead light in the ship's tiny surgery glowed brightly; the only sound in the room was the wheeze of the anaesthesia apparatus, the snap of clamps and the doctors' own quiet breathing as they worked desperately against time.

Dal felt as if he were in a dream, working like an automaton, going through mechanical motions that seemed completely unrelated to the living patient that lay on the operating table. In his training he had assisted at hundreds of organ transplant operations; he himself had done dozens of cardiac transplants, with experienced surgeons assisting and guiding him until the steps of the procedure had become almost second nature. On Hospital Earth, with the unparalleled medical facilities available there, and with well-trained teams of doctors, anaesthetists and nurses the technique of replacing an old worn-out damaged heart with a new and healthy one had become commonplace. It posed no more threat to a patient than a simple appendectomy had posed three centuries before.

But here in the patrol ship's operating room under emergency conditions there seemed little hope of success. Already the Black Doctor had suffered violent shock from the damage that had occurred in his heart. Already he was clinging to life by a fragile thread; the additional shock of the surgery, of the anaesthesia and the necessary conversion to the heart-lung machine while the delicate tissues of the new heart were fitted and sutured into place vessel by vessel was more than any patient could be expected to survive.

Yet Dal had known when he saw the second cardiogram that the attempt would have to be made. Now he worked swiftly, his frail body engulfed in the voluminous surgical gown, his thin fingers working carefully with the polished instruments. Speed and skill were all that could save the Black Doctor now, to offer him the one chance in a thousand that he had for survival.

But the speed and skill had to be Dal's. Dal knew that, and the knowledge was like a lead weight strapped to his shoulders. If Black Doctor Hugo Tanner was fighting for his life now, Dal knew that he too was fighting for his life—the only kind of life that he wanted, the life of a physician.

Black Doctor Tanner's antagonism to him as an alien, as an incompetent, as one who was unworthy to wear the collar and cuff of a physician from Hospital Earth, was common knowledge. Dal realized with perfect clarity that if he failed now, his career as a physician would be over; no one, not even himself, would ever be entirely certain that he had not somehow, in some dim corner of his mind, allowed himself to fail.

Yet if he had not made the attempt and the Black Doctor had died before help had come, there would always be those who would accuse him of delaying on purpose.

His mouth was dry; he longed for a drink of water, even though he knew that no water could quench this kind of thirst. His fingers grew numb as he worked, and moment by moment the sense of utter hopelessness grew stronger in his mind. Tiger worked stolidly across the table from him, inexpert help at best because of the sketchy surgical training he had had. Even his solid presence in support here did not lighten the burden for Dal. There was nothing that Tiger could do or say that would help things or change things now. Even Fuzzy, waiting alone on his perch in the control room, could not help him now. Nothing could help now but his own individual skill as a surgeon, and his bitter determination that he must not and would not fail.

But his fingers faltered as a thousand questions welled up in his mind. Was he doing this right? This vessel here ... clamp it and tie it? Or dissect it out and try to preserve it? This nerve plexus ... which one was it? How important? How were the blood pressure and respirations doing? Was the Black Doctor holding his own under the assault of the surgery?

The more Dal tried to hurry the more he seemed to be wading through waist-deep mud, unable to make his fingers do what he wanted them to do. How could he save ten seconds, twenty seconds, a half a minute? That half a minute might make the difference between success or failure, yet the seconds ticked by swiftly and the procedure was going slowly.

Too slowly. He reached a point where he thought he could not go on. His mind was searching desperately for help—any kind of help, something to lean on, something to brace him and give him support. And then quite suddenly he understood something clearly that had been nibbling at the corners of his mind for a long time. It was as if someone had snapped on a floodlight in a darkened room, and he saw something he had never seen before.

He saw that from the first day he had stepped down from the Garvian ship that had brought him to Hospital Earth to begin his medical training, he had been relying upon crutches to help him.

Black Doctor Arnquist had been a crutch upon whom he could lean. Tiger, for all his clumsy good-heartedness and for all the help and protection he had offered, had been a crutch. Fuzzy, who had been by his side since the day he was born, was still another kind of crutch to fall back on, a way out, a port of haven in the storm. They were crutches, every one, and he had leaned on them heavily.

But now there was no crutch to lean on. He had a quick mind with good training. He had two nimble hands that knew their job, and two legs that were capable of supporting his weight, frail as they were. He knew now that he had to stand on them squarely, for the first time in his life.

And suddenly he realized that this was as it should be. It seemed so clear, so obvious and unmistakable that he wondered how he could have failed to recognize it for so long. If he could not depend on himself, then Black Doctor Hugo Tanner would have been right all along. If he could not do this job that was before him on his own strength, standing on his own two legs without crutches to lean on, how could he claim to be a competent physician? What right did he have to the goal he sought if he had to earn it on the strength of the help of others? It was he who wanted to be a Star Surgeon—not Fuzzy, not Tiger, nor anyone else.

He felt his heart thudding in his chest, and he saw the operation before him as if he were standing in an amphitheater peering down over some other surgeon's shoulder. Suddenly everything else was gone from his mind but the immediate task at hand. His fingers began to move more swiftly, with a confidence he had never felt before. The decisions to be made arose, and he made them without hesitation, and knew as he made them that they were right.

And for the first time the procedure began to move. He murmured instructions to Jack from time to time, and placed Tiger's clumsy hands in the places he wanted them for retraction. "Not there, back a little," he said. "That's right. Now hold this clamp and release it slowly while I tie, then reclamp it. Slowly now ... that's the way! Jack, check that pressure again."

It seemed as though someone else were doing the surgery, directing his hands step by step in the critical work that had to be done. Dal placed the connections to the heart-lung machine perfectly, and moved with new swiftness and confidence as the great blood vessels were clamped off and the damaged heart removed. A quick check of vital signs, chemistries, oxygenation, a sharp instruction to Jack, a caution to Tiger, and the new prosthetic heart was in place. He worked now with painstaking care, manipulating the micro-sutures that would secure the new vessels to the old so firmly that they were almost indistinguishable from a healed wound, and he knew that it was going right now, that whether the patient ultimately survived or not, he had made the right decision and had carried it through with all the skill at his command.

And then the heart-lung machine fell silent again, and the carefully applied nodal stimulator flicked on and off, and slowly, at first hesitantly, then firmly and vigorously, the new heart began its endless pumping chore. The Black Doctor's blood pressure moved up to a healthy level and stabilized; the gray flesh of his face slowly became suffused with healthy pink. It was over, and Dal was walking out of the surgery, his hands trembling so violently that he could hardly get his gown off. He wanted to laugh and cry at the same time, and he could see the silent pride in the others' faces as they joined him in the dressing room to change clothes.

He knew then that no matter what happened he had vindicated himself. Half an hour later, back in the sickbay, the Black Doctor was awake, breathing slowly and easily without need of supplemental oxygen. Only the fine sweat standing out on his forehead gave indication of the ordeal he had been through.

Swiftly and clinically Dal checked the vital signs as the old man watched him. He was about to turn the pressure cuff over to Jack and leave when the Black Doctor said, "Wait."

Dal turned to him. "Yes, sir?"

"You did it?" the Black Doctor said softly.

"Yes, sir."

"It's finished? The transplant is done?"

"Yes," Dal said. "It went well, and you can rest now. You were a good patient."

For the first time Dal saw a smile cross the old man's face. "A foolish patient, perhaps," he said, so softly that no one but Dal could hear, "but not so foolish now, not so foolish that I cannot recognize a good doctor when I see one."

And with a smile he closed his eyes and went to sleep.