The underwater city of Euclidia is a weird and terrifying place, and it would seem almost impossible to escape from this well-guarded scientific colony 400 feet below the level of the South Pacific Ocean. It would be impossible for anyone depending on the mechanical devices protecting Euclidia, but the adventuring Gregory party escaped from the Magic Island with the help of their brave little homing pigeons, and now it appears that these same little birds may aid them again. The girl submarine commander, who has proven a friend in many instances, has informed Jerry and Joan that the homing pigeons are kept in the very laboratory where Captain Bradford will work with G-47. The great difficulty now will be how to plan the use of the pigeons without being overheard. Jerry and Joan are discussing this in their own quarters. Are you sure it's all right for us to talk now, Joan? We are quite safe. This small room is completely lined with Euclidean cloth. Then you're sure that if we put this cloth around the room carefully every time we want to talk in here that nobody's going to hear us? That is the situation. However, we must ascertain that the cloth is in perfect condition each time we use it. Huh? Well, what could happen to the cloth? You understand, do you not, that the soundproof qualities of this Euclidean cloth are contained not in the fabric of the cloth itself, but in the liquid with which the cloth is saturated. Oh, sure, I know that. It's just plain old cloth made of seaweed until they soak it in that secret formula there. Precisely. And that soundproofing liquid may be removed just as it is applied with another liquid. Gee whiz, Joan. You mean that one of those Euclideans might sneak in here while we're out in spoiler's cloth, take the soundproofing out of it, so we'd get caught next time we try to talk about something secret? That is precisely my meaning, Jerry. And I think it is only logical to expect such a move to be made. Yeah, well, I guess you're right. But now that we've got it all fixed up, let's figure out what we're going to do. I feel there is very little we can do until the captain is given the opportunity of working in the submarine laboratory with G-47 and locating the pigeons. Well, then he'll have to plan a way to smuggle one of them on board a submarine or a rocket ship with him on a test run so that he can get a chance to turn a pigeon loose within range of Los Angeles. How far will one of those little birds be able to fly and find my mother's home in Los Angeles? Well, that's the trouble, Joan, and that's the reason the captain's got to try to turn them loose pretty close to home. He's not sure how far they can make it now. At one time the captain told me he thought a thousand miles would be their limit. Well, that was all right then. They were just away from home a few weeks and they were in training all the time. But now they've been locked up in a strange place for a long time and they haven't had any practice. And Texas afraid that a few hundred miles is all they can possibly make. Then it will be necessary for the captain to arrange a long test run with a submarine or a rocket plane to release the pigeons within a short distance of Los Angeles. Yeah, that's it. And he will be closely guarded on those tests. Well, yes, but Texas figures yes and no on that. What do you mean yes and no? Well, G-47 knows that Texas is plenty smart about machinery and probably just as good a scientist as any of the rest of them. And when Texas is out with one of those ships testing it to find out what's wrong with it, G-47 is going to give him plenty of chance to do his stuff. Nevertheless, to carry a homing pigeon aboard with him and find the opportunity of releasing it without being observed will prove very difficult. Oh, but it's not that hard. Texas won't care if he's observed or not once the pigeon gets away. That is a mistake, Jerry. What's the mistake about it? I think we may consider that the release of the pigeon will be detected probably at the time it is released or surely within a very short time. Well, what of it? If the pigeon gets away, he's away and that's that. No, Jerry, as you would say, that is not that. Well, why isn't it? In the first place, if the pigeon is released from a rocket ship, which I consider most likely, the ship could easily overtake and destroy the little bird. Did you ever try catching a little bird going 40 miles an hour? Naturally not, did you? No, but I don't have to. You're the one that thinks it can be done. I see no reason why that should be particularly difficult, but in the event that fog or clouds allow the pigeon to safely lose itself, it would merely become necessary for one of the scientists to send a radio message to a Euclidean agent in Los Angeles, and the pigeon would be caught as Mr. Johnson waited for its arrival. Yeah, gee, I never thought of that. Johnson wouldn't even be waiting for its arrival. Johnson's like everybody else by now. He thinks we're all killed when that artificial volcano eruption made it look like the island was destroyed. Precisely. He will be expecting no communication from us, and the little bird may not find anyone ready to receive its message. Well, just the same. Tech figures that he can get a chance to use those pigeons to do us some good, and I think so too. I hope you are correct. Well, I know I am. In the meantime, let you and I plan a few things of our own. What do you wish me to do? Oh, help me think. Think about what? Think about escaping from this city in the cellar. That would only be a waste of time, except for the captain's daring plan we have no hope. Sometime I get so blame-sour at you that I could give you a good spanking. What is a spanking? Didn't you ever have one? No, Jerry, I have never had a spanking. Is it something I would like very much? No, it's something you wouldn't like very much. A spanking means that I turn you over my knee and paddle you good. Paddle? I have heard of paddle. That is the instrument with which a small boat is propelled through the water, is it not? Well, I wasn't thinking of just that kind of paddle, but maybe it's a good idea at that. Hello, children. Oh, Mother. Mrs. Gregory. What's the matter? You two seem surprised to see me. We are. I'll say we are. How did you get in here? How did I get in? You mean in this room? No, I mean in this apartment, this big place where all our rooms are. I simply walked in. Jerry, do you realize what that means? Boy, I'll say I do. It means that anybody else could have walked in just as easy and heard all we were saying. Were you discussing something you did not want overheard? Yes, Mother. We have covered this small closet with Euclidean cloth, as you can see, and we were discussing... Look out, Jones. If Mrs. Gregory walked in on us, anybody else could do the same thing. It was indeed stupid of us, Jerry. We should have realized that while this cloth was making this room soundproof, it was also making it impossible for us to hear anyone entering these chambers. I hope you haven't given away any of Tex's ideas. Oh, I guess we have if anybody was listening. Oh, Jerry. I think we are safe this time, Mother. Jerry and I have been speaking but a few moments, and you would probably have seen anyone leaving who might have overheard us. Yes, probably. But now that you have this little room fixed up so well, we'll continue using it with this added protection. When any two of us are discussing our plans, a third one must remain out in that other room on guard. You're right, Mrs. Gregory, and I hope it isn't too late for your idea to be of any good. I would not worry about that, Jerry. The element of time involved in our recent discussion should prove adequate protection. Yeah, we didn't talk long either. That is precisely what I said. Then you took too long to say it. Well, here you are. Oh, Tex. Sure happens quick. What's this? Now you can understand how startled Jerry and I were. I do understand, and I also understand how dangerous it is to speak in the false security of this room. What's going on here? Well, Joan and I covered the inside of this room with that Euclidean soundproof cloth, as you can see, and when we were talking in here, Mrs. Gregory popped in just like you did. You see, Tex, Jerry and Joan feel that someone else, someone from whom our plans should be concealed, could have walked in on them just as easily as I did. Oh, I see. That could happen. But remember that nobody would have overheard very much when you had these curtains drawn as they were when I came in. I never heard a sound until I stuck my head through these drapes you put up. Oh, boy. That's sure a relief. Nevertheless, I feel that one of us should remain in the outer chamber whenever we are discussing anything of value. By all means. Yes, it might be safer. I have a little something to plan with Jerry right now. Yes, Captain. No, not for the moment, Joan. I'll tell you and Pat later. Now, if you two ladies will get busy doing nothing out in the central room, Jerry and I can do a little planning and safety behind these curtains. Come, Joan, it's nearly time for lunch. We'll freshen up a bit. Very well, Mother. Do not be long, Jerry. Okay, Joan. We'll be there when the... Well, Jerry's voice was certainly cut off sharply when that curtain fell over the doorway. That cloth is perfectly soundproof. And Mother... Yes, dear? I think that should render our fears groundless. Well, what do you mean? Even if someone had entered and walked unheard to that door, as you and the Captain did, they could not have heard what we were saying without opening the curtains, as you did. Let's hope you're right. But remember, Joan, dear, there are a great many things about this weird underwater city that we know nothing about. Perhaps there's some way G-47 and the other scientists could overhear your conversation in that room. Of course, that is possible. But I do not think it is at all likely. Well, we can't help any by worrying about it. Come, dear, let's get ready for lunch. But I have not heard the luncheon signal yet. We will hear it any minute now. And then that table will start coming up through the floor. You know, I'd like to visit the kitchens here and see how they do it. I believe that could be easily arranged. We will ask G-47's permission. They must have a wonderful organization there. Food prepared for and served to nearly 300 people in a house and hour. That is sufficient time, is it not? Well, apparently it's quite enough here. But back home it wouldn't be long enough. I am afraid, Mother, that all things back home, as you call your world, must be forgotten. Now, now, Joan, that's no way to talk. Tex and Jerry are planning right now. And when those two get down to business, things usually happen. Jerry is very clever for one so young, is he not, Mother? Yes, he is. But most young people of that age are clever. Perhaps as clever as Jerry. Most of them never get a chance to show what they really can do. As older people insist on dictating to them, overruling them on everything, and molding them to older standards, whether they fit or not. Now, Tex isn't like that. He's always figured that anybody old enough to think and express their thoughts is old enough to have an opinion worth listening to. And when Jerry gets an idea, Tex listens. The Captain is a very fine and understanding man. You are quite fond of him, are you not, Mother? Why, uh, yes, Joan, I... Naturally, dear, I... Oh, Joan dear, come on, let's get ready for lunch. Mother, why do you always seem so nervous? And why do you wish to change the subject when I inquire into your feelings for the Captain? Now, Joan dear, we're too busy for that, and I... Oh, oh, there's the luncheon signal. Yes, and the steel slide is moving in the floor. Our luncheon table will be up in a few seconds. Perhaps you'd better go over there and tell Tex and Jerry that lunch is served. Surely they would know that. The signal is quite plain. But, uh, would they hear it behind the clock? Oh, how stupid of me, Mother! Of course not! I will call them at once. Captain Tex, Jerry, will you come... Mother! Yes, Joan? Come here, quickly! What is it, dear? Has something happened? Oh, that I do not know, but the Captain and Jerry are not here. Not here, let me see them. They're gone! But how, where? Is there any other opening to that room? Not that I have been able to locate. Only this small door and the walls, floor, and ceiling are of solid steel. But, Joan, two men just don't fade away through solid steel. Of course they do not. Nevertheless, they are gone and they did not come through the door. But where did they go and how? Joan, we must know what happened to them.