Back in the office he called Hallen again. And again Hallen answered. He sounded guilty and worried.

"I don't know whether I'm crazy or not," he said bitterly. "But I was in your office. I saw your secretary there--and she didn't feel pins stuck in her. And something did happen to those Bulgarians that the Greeks don't know anything about, or the Americans either. So you're to tell your story to the high bra.s.s down in Athens. I think you'll be locked up afterward as a lunatic--and me with you for believing my own eyes. But a plane's being readied."

"Where do I meet you?" asked Coburn.

Hallen told him. A certain room out at the airport. Coburn hung up. The telephone rang instantly. He was on the way out, but he turned back and answered it. Janice's voice--amazingly convincing--came from the instrument. And at the first words his throat went dry. Because it couldn't be Janice.

"I've been trying to get you. Have you tried to reach me?"

"Why, no. Why?"

Janice's voice said: "I've something interesting to tell you. I left the office an hour ago. I'm at the place where I live when I'm in Salonika.

Write down the address. Can you come here? I've found out something astonishing!"

He wrote down the address. He had a feeling of nightmarishness. This was not Janice--

"I'm clearing up some matters you'll guess at," he said grimly, "so I may be a little while getting there. You'll wait?"

He hung up. And then with a rather ghastly humor he took some pins from a box on the desk and worked absorbedly at bending one around the inside of the band of the seal ring he wore on his right hand.

But he didn't go to the telephoned address. He went to the Breen Foundation. And Janice was there. She was the real Janice. He knew it instantly he saw her. She was panic-stricken when he told her of his own telephone experience. Her teeth chattered. But she knew--instinctively, she said--that he was himself. She got into the cab with him.

They reached the airport and found the office Hallen had named. The lettering on it, in Greek and French, said that it was a reception room for official visitors only.

"Our status is uncertain," said Coburn drily. "We may be official guests, or we may be crazy. It's a toss-up which status sticks."

He opened the door and looked carefully inside before he entered. Hallen was there. There was a lean, hard-bitten colonel of the American liaison force in Greece. There was a Greek general, pudgy and genial, standing with his back to a window and his hands clasped behind him. There were two Greek colonels and a major. They regarded him soberly.

"Howdo, Coburn," said Hallen painfully. "You're heading for Athens, you know. This is Miss Ames? But these gentlemen have ... ah ... a special concern with that business up-country. They'd like to hear your story before you leave."

"I suppose," said Coburn curtly, "it's a sort of preliminary commission in lunacy."

But he shook hands all around. He kept his left hand in his coat pocket as he shook hands with his right. His revolver was in his left-hand pocket now too. The Greek general beamed at him. The American colonel's eyes were hard and suspicious. One of the two Greek colonels was very slightly cross-eyed. The Greek major shook hands solemnly.

Coburn took a deep breath. "I know my tale sounds crazy," he said, "but ... I had a telephone call just now. Hallen will bear me out that my secretary was impersonated by somebody else this afternoon."

"I've told them that," said Hallen unhappily.

"And something was impersonating Dillon up in the hills," finished Coburn. "I've reason to believe that at this address"--and he handed the address he'd written down to Hallen--"a ... creature will be found who will look most convincingly like Miss Ames, here. You might send and see."

The American colonel snorted: "This whole tale's preposterous! It's an attempt to cash in on the actual mystery of what happened up-country."

The Greek general protested gently. His English was so heavily accented as to be hard to understand, but he pointed out that Coburn knew details of the event in Naousa that only someone who had been there could know.

"True enough," said the American officer darkly, "but he can tell the truth now, before we make fools of ourselves sending him to Athens to be unmasked. Suppose," he said unpleasantly, "you give us the actual facts!"

Coburn nodded. "The idea you find you can't take is that creatures that aren't human can be on Earth and pa.s.s for human beings. There's some evidence on that right here." He nodded to the Greek major who was the junior officer in the room. "Major, will you show these other gentlemen the palm of your hand?"

The Greek major frowned perplexedly. He lifted his hand and looked at it. Then his face went absolutely impa.s.sive.

"I'm ready to shoot!" snapped Coburn. "Show them your hand. I can tell now."

He felt the tensing of the others in the room, not toward the major but toward him. They were preparing to jump him, thinking him mad.

But the major grinned ruefully: "Clever, Mr. Coburn! But how did you pick me out?"

Then there was a sensation of intolerable brightness all around. But it was not actual light. It was a sensation inside one's brain.

Coburn felt himself falling. He knew, somehow, that the others were falling too. He saw everyone in the room in the act of slumping limply to the floor--all but the Greek major. And Coburn felt a bitter, despairing fury as consciousness left him.

IV

He came to in a hospital room, with a nurse and two doctors and an elaborate oxygen-administering apparatus. The apparatus was wheeled out.

The nurse followed. The two doctors hurried after her. The American colonel of the airport was standing by the bed on which Coburn lay, fully dressed.

Coburn felt perfectly all right. He stirred. The American colonel said sourly: "You're not harmed. n.o.body was. But Major Pangalos got away."

Coburn sat up. There was a moment's bare trace of dizziness, and that was gone too. Coburn said: "Where's Miss Ames? What happened to her?"

"She's getting oxygen," said the colonel. "We were rushed here from the airport, sleeping soundly just like those Bulgarians. Major Pangalos ordered it before he disappeared. Helicopters brought some Bulgarians down, by the way, and oxygen brought them to. So naturally they gave us the same treatment. Very effective."

The colonel looked both chastened and truculent. "How'd you know Major Pangalos for what he was? He was accepted everywhere as a man."

"His eyes were queer," said Coburn. He stood up experimentally. "I figured they would be, if one looked. I saw the foam suit that creature wore up-country, when he wasn't in it. There were holes for the eyes. It occurred to me that his eyes weren't likely to be like ours. Not exactly. So I hunted up the real Dillon, and his eyes weren't like I remembered. I punched him in the nose, by the way, to make sure he'd bleed and was human. He was."

Coburn continued, "You see, they obviously come from a heavy planet and move differently. They're stronger than we are. Much like the way we'd be on the moon with one-sixth Earth gravity. They probably are used to a thicker atmosphere. If so, their eyes wouldn't be right for here. They'd need eyegla.s.ses."

"Major Pangalos didn't--"

"Contact eyegla.s.ses," said Coburn sourly. "Little cups of plastic. They slip under the eyelids and touch the white part of the eye. Familiar enough. But that's not all."

The American colonel looked troubled. "I know contact lenses," he admitted. "But--"

"If the Invaders have a thick atmosphere at home," Coburn said, "they may have a cloudy sky. The pupils of their eyes may need to be larger.

Perhaps they're a different shape. Or their eyes may be a completely alien color. Anyhow, they need contact lenses not only to correct their vision, but to make their eyes look like ours. They're painted on the inside to change the natural look and color. It's very deceptive. But you can tell."

"That goes to Headquarters at once!" snapped the colonel.

He went out briskly. Coburn followed him out of the room to look for Janice. And Janice happened to be looking for him at exactly the same moment. He was genuinely astonished to realize how relieved he was that she was all right.

He said apologetically: "I was worried! When I felt myself pa.s.sing out I felt pretty rotten at having failed to protect you."

She looked at him with nearly the same sort of surprised satisfaction.