“Do you think it will be unlocked?” Bill dropped his voice to a whisper. The three were standing on the landing at the head of the stairs, facing the door.

“Sure to be,” returned Terry. “That is, if we can take friend Peters’ word for it. He spilled all this dope when he’d had an argument with the rest of the gang.”

“Then let’s go—” said Bill. “You stand to one side, Dorothy.”

“Shucks!” With a twist of the handle, that young lady threw the door wide and jumped into the room.

“Hands up! Stick ’em up!” she cried.

Two of the three men seated at the table complied at once with her command. Their hands shot above their heads with the rapidity of lightning. The third reached for a revolver that lay amongst the scattered cards.

“Bang!”

The man gave a cry of pain and caught at his shattered wrist with his other hand.

Startled by the sudden detonation just behind her, Dorothy almost dropped her gun.

“Dog-gone it!” Terry seemed annoyed.

“What’s the matter?” Bill still covered the men.

“Matter enough! Too much rest cure, I guess. Forgot to remove the safety catch on this gat you gave me. Lucky you fired when you did.”

“Well, never mind that now,” Bill’s words were crisp and to the point. “Grab that clothesline and tie their hands behind their backs. That’s right! Dorothy, will you give first aid to that fellow’s wrist? I’ll see that they don’t play any tricks.”

After securing the men, Terry searched their clothes and produced two revolvers and a wicked looking knife. He also took a ring of keys from Peters.

“Gee!” exclaimed that gentleman. “If it ain’t the girl what blame near kicked me teeth out I’ll eat me bloomin’ hat!”

“You’ll eat skilly in Wethersfield Prison, or Atlanta, before you get through,” Terry promised. “Shake a leg—both of you. Down to the cells for yours. Did you ever realize what a swell difference there is between the titles of jailer and prisoner? March!”

“Wait a minute!” Dorothy cut in. “I’ll help you take this man along, too. I’ve done all I can for him. It’s a clean hole through his wrist. Bone’s broken but the bullet missed the artery. He might be worse off.”

Bill spoke from the doorway that led into the rest of the house. “While you’re gone I’ll search this place for any other members that might otherwise be overlooked!”

After housing the smugglers in cells, Dorothy and Terry returned to the kitchen and were surprised to find Bill speaking over the telephone.

“And that’s that, Dad,” they heard him say. “Spread the good tidings in proper places and make it snappy, please. Bye-bye!”

He placed the receiver on its hook.

“I guess you got that,” he smiled. “Dad will phone the police and Washington. Then he’s driving over here with Frank. And he will also let Mr. Walters and your father know, Dorothy.”

“Fine—I’m glad he thought of that!” Dorothy laughed in excited approval.

“Didn’t take you long to search the place,” said Terry.

“No—only a few rooms on this floor are being used. The staircase is thick with dust. Nobody up there—no footprints.”

“Well, what’s to do now?”

“We’ll wait for Dad, of course,” said Bill, “and then Dorothy and I can fly our respective planes home. How about it, pal? Feel able to do that?”

Dorothy lifted her eyebrows in derision. “Well, I should hope so! I suppose I do look pretty frazzled—but you don’t seem in the best condition yourself. However—I’ve another plan.”

“What’s that?”

Terry had taken over the phone and was talking in low tones to his mother.

“Do you remember I told you I had a hunch, Bill?”

“Yes, I do. What about it?”

“We’re going to follow my hunch.”

“Where to?”

“Well, we’ll start out of this house—by the front door this time, if you please—then across the meadow and through the wood to the field where our planes are parked.”

“And—?”

“And then you’re going to get into the rear cockpit of Will-o’-the-Wisp and take a little hop with me.”

Bill looked surprised. “What about my Ryan?”

“Oh, Frank can pilot her home.”

“Yes? And then where are we going?”

“That’s my secret. Tell Terry, and come along now. We’re in a hurry, even if you don’t know it.”

“Well, I’m evidently not supposed to know anything of this new mystery!”

“Don’t be stuffy! Come on, now. This is serious, Bill, really, I’m not leading you on a wild goose chase, I promise you.”

“Humph! It must be hot stuff—not!”

Dorothy made a face at him. “I want to tell you it’s the hottest stuff of the whole business. And I just want you to be in at the finish, don’t you see, stupid?”

“All right. As you insist—”

“That’s right. Of course I do. And when we’ve done this thing up brown, I’ll cart you back home to dinner—and if you are very good you can sit next to me!”

Bill grinned. “You may be New England Yankee, but that line of blarney you hand out spells Ireland in capital letters! Come on then, we’ll leave Terry to guard the fort.”

After they had put that young man wise to their plans, the two left the Castle. They were both pretty nearly exhausted after their experiences in the tunnel, but the success of their adventure was elating, and more than made up for its bad effects.

“Well, here’s the field just where we left it,” announced Bill as he helped Dorothy over the stone fence. “And there’s that Willy plane of yours, too. Whither away?”

“Hop in and you’ll see.”

Five minutes later, Bill looked down from his seat in the rear cockpit and saw that she was going to land near the tennis courts in the broad parking space behind the cabanas at the beach club. The members had become used to seeing her land Will-o’-the-Wisp on the club grounds. Their descent therefore caused little or no notice. The plane stopped rolling and a man in the club uniform of a beach attendant ran up.

“Hello, Jeffries,” waved Bill. “I thought you might be here. How are things?”

“We caught Donovan and Charlie Myers over at Babylon. But they’re small fry. Anything new, Bolton?”

Bill got out of the plane and helped Dorothy to descend.

“I should say there is! Tell you about it in a minute. Dorothy, let me present Mr. Arthur Jeffries, one of the very big men of the United States Secret Service. Arthur, this is the famous Dorothy Dixon!”

Arthur Jeffries said some polite things which caused Dorothy to blush modestly, and in a few pithy sentences Bill told the story of their afternoon.

“So you see, old man,” he ended. “You won’t have to wait around this club any longer disguised as a goldfish or what have you—because the bearded aviator won’t fly the Mystery Plane over here any more—that is to say—not for twenty years or so at the soonest.”

“He’ll get all that or more,” Jeffries commented crisply. “But the man he worked for—sunning himself over there on the sand—old Holloway, I mean—he’s the nigger in the woodpile! The boss of this gang of diamond smugglers—but I can’t arrest him on that evidence!”

Dorothy made an eager gesture. “Will you come with me—I want to show you two something. We’ll go around the far side of that big cabana on the end of the boardwalk. We’re going inside.”

“Holloway’s bath house?” This from Bill.

“Exactly. I don’t want him to see us, though, so be careful.”

The three rounded the gaily painted cottage and ducking under the red and black striped awning, entered the front room which was fitted out with the usual wicker furniture and bright rugs.

“I wonder where he keeps them,” Dorothy murmured to herself. “Ah—this looks like it!”

She lifted the hinged lid of a handsome sea chest and pulled forth a dozen or more colored flags.

“By jove! The goods!” cried Bill. “How did you ever guess it, Dot?”

Dorothy was so pleased by her find that she passed over his use of the despised diminutive.

“I just happened to remember that he generally decked out his cabana with a flock of these things. And though the club runs up flags on special occasions, Mr. Holloway did it nearly every afternoon. It came to me when you pulled off Tracey’s beard back there in the tunnel.”

“Precisely,” said Arthur Jeffries. “Holloway would get word in New York at his office, probably, when a liner carrying contraband was expected off Fire Island light. Then he’d come out here and signal the time to Tracey in his airplane, by means of these flags. I’ll bet the old boy never went near that Castle. Some alibi! He and Tracey probably never saw each other from the time he went to the city in the morning until he came home for dinner at night.”

“Are you going to arrest him now?” she asked breathlessly.

“As soon as I can get out on the beach. I’ll do it as quietly as possible, of course. No use in causing a disturbance with his friends around. So long, Bill. Glad to have met you, Miss Dixon—and many thanks. See you both later on.”

They left the cabana with him, but turned back toward the plane as he went down the beach.

“That ties it, I guess,” she smiled.

“It certainly does!” agreed Bill.

“Now—didn’t I tell you it would be hot stuff?”

He looked at her and they both burst out laughing.

“And the best of it is that the government will probably pin a medal on you for it!” he declared.

“Oh, Bill! Do you really think that?”

Bill grinned at her excitement. “You get into that plane and take me home to dinner. That was the bargain, and I’m famished!”

“Dinner!” exclaimed Dorothy in disgust. “My word! We’ve caught those diamond smugglers when the whole of the Secret Service couldn’t do it—and all you think of is food! Gee, I’m glad I’m not a mere man. Hop aboard. I’ll give her the gun and fly you home to your dinner.”

Those who enjoyed this story and the preceding one entitled Dorothy Dixon Wins Her Wings will find much to interest them in the next book of this series entitled Dorothy Dixon Solves the Conway Case.