"It's spotted. I'm giving you free motion if you want to use it."
The feel of the ship changed. It no longer descended. The landing-grid operator was holding it aloft, but Calhoun could move it in evasive action if he wished. He approved the liberty given him. He could use his emergency rockets to dodge. A second thread of smoke came streaking upward.
Then other threads of white began just outside the landing grid. They rushed after the first. The original rockets seemed to dodge. Others came up. There was an intricate pattern formed by the smoke trails of rockets rising and other rockets following, and some trails dodging and others closing in. Calhoun carefully reminded himself that it was not likely that there'd be atomic war heads. The last planetary wars had been fought with fusion weapons, and only the crews of single ships survived. The planetary populations didn't. But atomic energy wasn't much used aground, these days. Power for planetary use could be had more easily from the upper, ionized limits of atmospheres.
A pursuing rocket closed in. There was a huge ball of smoke and a flash of light, but it was not brighter than the sun. It wasn't atomic flame. Calhoun relaxed. He watched as every one of the first-ascended rockets was tracked down and destroyed by another. The last, at that, was three-quarters of the way up.
The Med Ship quivered a little as the force fields tightened again. It descended swiftly. It came to ground. Figures came to meet Calhoun as, with Murgatroyd, he went out of the air lock. Some were uniformed. All wore the grim expression and harried look of men under long-continued strain.
The landing-grid operator shook hands first.
"Nice going! It could be lucky that you arrived. We normals need some luck!"
He introduced a man in civilian clothes as the planetary Minister for Health. A man in uniform was head of the planetary police. The others weren't introduced.
"We worked fast after your call came!" said the grid operator. "Things are lined up for you, but they're bad!"
"I've been wondering," admitted Calhoun dryly, "if all incoming ships are greeted with rockets."
"That's the paras," said the police head, grimly. "They'd rather not have a Med Service man here."
A ground car sped across the spaceport. It came at a headlong pace toward the group just outside the Med Ship. There was a sudden howl of a siren by the spaceport gate. A second car leaped as if to intercept the first. Its siren screamed again. Then bright sparks appeared near the first car's windows. Blasters rasped. Incredulously, Calhoun saw the blue-white of blaster bolts darting toward him. The men about him clawed for weapons. The grid operator said sharply:
"Get in your ship! We'll take care of this! It's paras!"
But Calhoun stood still. It was instinct not to show alarm. Actually, he didn't feel it. This was too preposterous! He tried to grasp the situation and fearfulness does not help at such a time.
A bolt crackled against the Med Ship's hull just beyond him. Blasters rasped from beside him. A bolt exploded almost at Calhoun's feet. There were two men in the first-moving ground car, and now that another car moved to head them off, one fired desperately and the other tried to steer and fire at the same time. The siren-sounding car send a stream of bolts at them. But both cars jounced and bounced. There could be no marksmanship under such conditions.
But a bolt did hit. The two-man car dipped suddenly to one side. Its fore part touched ground. It slued around, and its rear part lifted. It flung out its two passengers and with an effect of great deliberation it rolled over end for end and came to a stop upside down. Of its passengers, one lay still. The other struggled to his feet and began to run—toward Calhoun. He fired desperately, again and again——
Bolts from the pursuing car struck all round him. Then one struck him. He collapsed.
Calhoun's hands clenched. Automatically, he moved toward the other still figure, to act as a medical man does when somebody is hurt. The grid operator seized his arm. As Calhoun jerked to get free, that second man stirred His blaster lifted and rasped. The little pellet of ball-lightning grazed Calhoun's side, burning away his uniform down to the skin, just as there was a grating roar of blaster fire. The second man died.
"Are you crazy?" demanded the grid operator angrily. "He was a para! He was here to try to kill you!"
The police head snapped:
"Get that car sprayed! See if it had equipment to spread contagion! Spray everything it went near! And hurry!"
There was silence as men came from the spaceport building. They pushed a tank on wheels before them. It had a hose and a nozzle attached to it. They began to use the hose to make a thick, foglike, heavy mist which clung to the ground and lingered there. The spray had the biting smell of phenol.
"What's going on here?" demanded Calhoun angrily. "Damnation! What's going on here?"
The Minister for Health said unhappily:
"Why ... we've a public-health situation we haven't been able to meet. It appears to be an epidemic of ... of ... we're not sure what, but it looks like demoniac possession."
II
"I'd like," said Calhoun, "a definition. Just what do you mean by a para?"
Murgatroyd echoed his tone in an indignant, "Chee-chee!"
This was twenty minutes later. Calhoun had gone back into the Med Ship and treated the blaster burn on his side. He'd changed his clothing from the scorched uniform to civilian garb. It would not look eccentric here. Men's ordinary garments were extremely similar all over the galaxy. Women's clothes were something else.
Now he and Murgatroyd rode in a ground car with four armed men of the planetary police, plus the civilian who'd been introduced as the Minister for Health for the planet. The car sped briskly toward the spaceport gate. Masses of thick gray fog still clung to the ground where the would-be assassins' car lay on its back and where the bodies of the two dead men remained. The mist was being spread everywhere—everywhere the men had touched ground or where their car had run.
Calhoun had some experience with epidemics and emergency measures for destroying contagion. He had more confidence in the primitive sanitary value of fire. It worked, no matter how ancient the process of burning things might be. But very many human beings, these days, never saw a naked flame unless in a science class at school, where it might be shown as a spectacularly rapid reaction of oxidation. But people used electricity for heat and light and power. Mankind had moved out of the age of fire. So here on Tallien it seemed inevitable that infective material should be sprayed with antiseptics instead of simply set ablaze.
"What," repeated Calhoun doggedly, "is a para?"
The Health Minister said unhappily:
"Paras are ... beings that once were sane men. They aren't sane any longer. Perhaps they aren't men any longer. Something has happened to them. If you'd landed a day or two later, you couldn't have landed at all. We normals had planned to blow up the landing grid so no other ship could land and be lifted off again to spread the ... contagion to other worlds. If it is a contagion."
"Smashing the landing grid," said Calhoun practically, "may be all right as a last resort. But surely there are other things to be tried first!"
Then he stopped. The ground car in which he rode had reached the spaceport gate. Three other ground cars waited there. One swung into motion ahead of them. The other two took up positions behind. A caravan of four cars, each bristling with blast weapons, swept along the wide highway which began here at the spaceport and stretched straight across level ground toward the city whose towers showed on the horizon. The other cars formed a guard for Calhoun. He'd needed protection before, and he might need it again.