The dawn sun was still out of sight far down below the eastern lip of the world. Not even the first faint glow of its coming could be seen in the sky. On the tarmac of Eighty-Four's field three powerful Mark 5 Spitfires were being warmed up and mothered by mechanics as though they were infant babes in arms. Off to one side, Dave Dawson, Freddy Farmer, Barker, and Squadron Leader Markham, stood waiting and talking of everything under the sun except the special patrol that was soon to get underway.

That was a taboo subject with them. It was for the simple reason there wasn't anything else to discuss. All the plans and preparations had been made. Special high speed cameras, that could be operated from the control stick, had been fitted in the planes. The cameras had been tested and found to be in perfect working order. Each pilot had taken his plane aloft and tested it until he was thoroughly satisfied with every beat of the engine, and every single response to a touch on the controls. Everything that could be done, had been done. There was nothing to do now but wait for the engines to be warmed up ... and then get on with the job.

"Say, Barker," Dave suddenly broke a minute's silence. "Meant to speak to you about this, but we've all been pretty busy. I mean.... Well, darn it, you're still senior officer, and I'm perfectly willing for you to take over command of this show. Fact is, I think it would be a sensible idea. I...."

"Oh, no you don't, Yank!" Barker cried and laughed. "Decent and mighty sporting of you, old bean. And I like you a lot for saying it. But I've been in command of special shows before. Not at all to my liking. Hate responsibility, you know. I'm always getting things messed up something terrible."

"Yeah, I can guess!" Dave snorted. "He's won the Distinguished Flying Cross, and bar! And he says he'd mess things up? Nix on that line, friend. But I really am serious about your...."

"Don't be!" Barker said firmly. "I refuse, flatly. No, my lad. I'm going to tag along obeying orders on this show. And love it, I fancy."

"Then you won't...?" Dave started again and hesitated.

"No!" Barker repeated. "Absolutely not. If it's a success then you get perhaps the Victoria Cross, my lad. If it's not, then you get Squadron Leader Markham on your neck. I don't! See what I mean, old thing?"

Dave grinned and looked at his commanding officer who was shaking with laughter.

"Don't mind Barker, Dawson," the O.C. said. "He's an awful one for juggling the truth. Frankly, I've never so much as spoken a harsh word to him since he's been in the squadron."

"But, what you've thought, sir!" Barker said and laughed. "Just the same, Dawson, this is your show. And in my opinion you certainly deserve to have command."

"Well, I still don't know about that," Dave said with a shrug. "But.... Hold everything! That's a ship coming down to land, isn't it?"

All eyes were turned on the star studded sky overhead whence had come the sudden sound of airplane engines. An instant later the sound died down to a purr. And a brief moment after that the darkness was cut by the twin beams of the incoming plane's landing lights.

"Can't see for those darn lights," Dave grunted. "But she sounds to me like a Blenheim."

"It is!" Freddy Farmer echoed. "I can see her, now. I say! That's the same bus Group Captain Ball, and Colonel Trevor, came down in from London. I wonder if they're coming back."

"I wonder, too!" Squadron Leader Markham echoed. And Dave thought he caught just a faint trace of hopefulness in the O.C.'s voice. "Maybe they've decided to wash-out the patrol. Maybe something else has popped up."

As Dave watched the shadowy blur slide down toward the surface of the field, then level off and settle gently, a conglomeration of mixed emotions surged through him. One instant he experienced the familiar eerie tingling at the back of his neck that was always an advance warning of danger just ahead. Then in the next instant a sense of disappointment would flood through him. As though that plane was bringing word that the flight over occupied France had been called off. Then again he was filled with the strange excited feeling of more mystery being added to what already existed. A jumble of emotions and crazy thoughts that plagued him as he waited for the pilot of the Air Ministry Blenheim to taxi up to the line.

When the plane stopped, and the door was popped open, only one man jumped down onto the ground. That man was Colonel Trevor, and he hurried over to the group with a look of marked relief quite visible on his face in the pale glow shed by the two or three flare lights set about on the tarmac.

"Thank heavens, you haven't taken off yet!" the Intelligence officer cried. "Didn't want to waste time trying to get you on the phone. Raid on in London, anyway, and the phone service isn't so good at such times. No, not a hot raid. Just a few Jerry ships up there. And our lads are handling them very nicely. Anyway, I dashed out to Croydon in the blasted black-out and commandeered Ball's plane. I've got a bit more information for you, Dawson. By the way, do you know that terrain between Boulogne and Lille?"

"Fairly well, sir," the Yank R.A.F. ace replied. "I've done quite a bit of flying over that section, now and again. Why, sir?"

The Intelligence officer didn't answer at once. He fished a hand into the pocket of his tunic and pulled out a folded sheet of paper. Smoothing it out he held it to the light so that all could see. A map had been roughly drawn in pencil on the paper.

"A map of a three square mile spot of ground exactly seven miles west of Lille," Colonel Trevor said, and started pointing things out with his finger. "See this? A hill range. Here is the Lille River that flows into the Somme farther south. See this sharp bend in the river? Well, the ground there is thickly wooded, and to the east ... the southeast, rather ... is quite an expanse of swamp ground. Now, just a shade east of the edge of that swamp land is a tiny French village. You can't even find it on a map, but its name is Fleurville. Somewhere in that area, Dawson, is the secret weapon that Hitler plans to use against us. The weapon, I am sure, that destroyed those Lockheed Hudson bombers last Tuesday night."

Dave didn't say anything as the Intelligence officer stopped speaking. He stared hard at the pencil drawn map in an effort to stamp every little detail on his mind. Squadron Leader Markham, however, was not so interested in the map as he was in what Colonel Trevor had said.

"Why do you say that, Colonel?" he asked. "And where did you get this map?"

"I traced that map from one you could only see under a microscope," the other said. "From a map originally drawn almost pin head size by my brother."

Dave jerked his head up, eyes wide.

"Your brother, sir?" he gasped. "But your brother's dead! You mean another communication came through just the same? That he'd sent it on its way before he was captured?"

"No," Colonel Trevor said quietly. "My brother brought it with him. Remember my not wanting anybody to touch the body? Remember my saying something about an autopsy? Well, naturally, I did not plan for any autopsy to be made on my brother. The cause of his death was clear enough. However, in Intelligence every agent has a special way of hiding secret messages in the event he is captured. Some use false fingernails with the message printed underneath too small for the human eye to read. Others conceal the message under a false patch of hair glued to their scalp. And so on. There are a hundred and one different ways of hiding information you've gathered. However, each man's method is a secret between himself and the Chief of Intelligence. Therefore I didn't allow your medico to touch my brother. I wanted to communicate with my Chief first."

Colonel Trevor paused for a moment, squared his jaw a bit, and then continued.

"My brother did bring back information," he said. "His method of hiding messages on his person was by means of a hollowed out false tooth that not more than one dentist in a hundred would detect. In that hollow tooth was a postage stamp size original of this map, and some instructions."

"Dope on the secret Nazi weapon, sir?" Dave asked eagerly as the Intelligence officer paused again.

"Some," was the quiet reply, "but not nearly enough. To be perfectly truthful, my brother still didn't get complete details. He only learned that somewhere in this area covered by the map the Nazis have installed this new weapon, and...."

Colonel Trevor cut himself off short and nodded at Dave.

"Your hunch was a good one, Dawson," he said. "According to my brother's report, the Nazis have installed the weapon there for the purpose of experiments and tests. As I said, he did not know what the weapon is. He was only able to find out that it is to be used primarily against aircraft."

"Not against troops?" Freddy Farmer spoke up. "Then how do they expect to beat off an invasion attempt. They...! That's rather silly of me, isn't it?"

"What, Farmer?" Squadron Leader Markham asked with a puzzled frown.

"The question, sir," the English youth replied and blushed faintly. "I suddenly realized that the answer is obvious. This war has proved that the side that has control of the air is the side that comes out on top. So, if the Nazis are able to maintain control of the air over Occupied Europe, all the invasion troops in the world wouldn't of much use to us."

"Right, Freddy!" Dave said with a grin. "Go to the head of the class, my boy. Did you learn anything else, Colonel?"

"Sorry, but that's all, Dawson," the Intelligence officer replied. "But it should help you a little. At least you won't have to waste time buzzing around over the entire area. Concentrate on the spots covered by this map. Here, better take my copy along with you. Well.... Well, good luck, chaps. And God speed back home again."

Colonel Trevor didn't thrust out his hand, or stiffen to attention and salute the three R.A.F. aces. He did nothing but look at them each in turn. That was plenty. His eyes said far more than his lips could have said. Expressed far more than any firm hand shake or slap on the back.

"Thanks, sir," Dave said for the three of them. "You can depend on us to bring back the pictures ... or else."

"Never mind the, or else, Dawson," Squadron Leader Markham grunted. "Just make sure all three of you come back! And, Dawson?"

"Yes, sir?" Dave murmured.

Squadron Leader Markham didn't speak for a few seconds. He stood staring Dave straight in the eye. Then suddenly he raised a cautioning finger.

"In case things don't turn out as you hope," he said eventually. "In case the patrol looks like a complete wash-out, don't get too many of those hunches of yours, will you? There'll always be a tomorrow in this blasted war, you know. Don't try to win it in a few hours, though goodness knows you and Farmer could probably make a fairly good go at it."

"Don't worry, sir," Dave chuckled and tightened the strap on his helmet. "I'll watch my step, and try not to lead with my chin. But if I should get out of line you can count on Barker and Farmer to throw a halter on me."

"Oh, quite!" Flight Lieutenant Barker echoed. "I don't fancy to step out of this war for quite some time, if ever. Don't worry, sir, Farmer and I will keep an eye on this wildman from the States."

"And a good grip with both hands, too, sir!" Freddy added. "But, I've handled the balmy blighter before, and I can do it again."

"Shucks!" Dave said in mock disappointment. "Then what's the sense of my going along, if I can't have fun?"

"Personally, I wish there was no sense in any of you going along," Squadron Leader Markham said gravely. "However, war's war, and that's that. I guess it's time for you to be off. The very best, lads! And happy landings ... on this field!"

The trio hesitated a moment, looked at each other, and then as one man turned and walked over to their planes. As Dave climbed into his pit a soothing calm flowed through his body. The calm before the storm, perhaps. But for the moment the excitement of the occasion, the tingling, eager anticipation of things to come, and the myriad little inner fears and doubts, were banished. It was as though he were climbing into his Mark 5 to take it aloft for a joy hop, or a bit of gunnery practice on the field's ground target. That soon he would be leading Freddy Farmer and Barker deep into mystery skies over occupied Europe was as something as far removed as the sun.

A sense of peace and contentment were his as he settled himself in the pit, and made a last minute check of everything. But perhaps the war gods were perfectly willing that he should feel that way for a spell. They knew it would not last long. They knew what awaited those three stout hearted aces of the R.A.F. They knew what was waiting, and what was going to happen. And they clapped their hands and nudged each other in high glee.

"Well, there'll always be an England," Dave murmured and reached for the throttle. "So, I'll be seeing you soon!"

Five seconds later three Spitfire Mark 5s thundered out across the field, cleared, and went zooming up to lose themselves quickly in the shadowy sky. Back down on the tarmac Squadron Leader Markham stood like a carved statue, his eyes still turned upward toward the half night, half dawn sky. He saw nothing but murky shadows, but the drone of three powerful Rolls-Royce engines was still in his ears. He listened until the sound faded away in the distance. Then slowly he clenched both fists and turned to look at Colonel Trevor.

"If they don't come back," he said in a strained voice, "I fancy you and Group Captain Ball had better catch the first boat for South Africa!"

"Amen!" the Intelligence officer said softly.