“Dorothy, have you ever done anything in the way of amateur theatricals?” Ashton Sanborn stroked the bowl of his pipe reflectively.

“Why—er—yes, a little.” She looked a bit bewildered. “I’ve been in the Silvermine Sillies for the past two years.”

Sanborn nodded. “How is it you’re out of school on a Thursday?” The question seemed irrelevant. He was leaning back in his chair now, surveying the ceiling rather absently, but there was nothing lackadaisical about his crisp tones.

“Christmas holidays. Why?”

“Because, if you’re willing, I may want you to work for me for a few days. I suppose I can reach your father by telephone at the New Canaan bank?”

“No, you can’t—Daddy is down in Florida on a fishing trip. He’s on Mr. Bolton’s yacht, somewhere off the coast. They won’t be back until Christmas Eve.”

“That,” said the Secret Service man, “complicates matters. Who, may I ask, is looking after Miss Dixon while Mr. Dixon is away?”

“I’m looking after my own sweet self, sir.” Dorothy grinned roguishly.

“Then who is to take the responsibility for your actions, young lady?”

“Why, you may—if you want to!”

For a moment or two the detective studied her thoughtfully. There was a certain assurance about this girl’s manner, a steely quality that came sometimes into her grey eyes, an indefinable air of strength and quiet courage—

“Do you think you could impersonate your cousin, Dorothy?”

“Why—of course!” Dorothy showed her surprise. “We look exactly alike. Didn’t Howard take me for Janet?”

“He did—but from what he has told us about her, your natures are entirely different. Janet, from all accounts, is a rather meek and demure young lady. Remember, that in order to convince anyone who knows her you would have to submerge your own personality in hers. And nobody would ever describe you as a meek, demure young lady!”

“An untamed wildcat—if you ask me,” chuckled Bill.

“Why, thanks a lot, William!” Dorothy’s hearers were abruptly aware of the changed quality of her voice as she continued to speak in melting tones of pained acceptance. “But nobody did ask you, darling, so in future when your betters are conversing, be good enough to button up that lip of yours!” She finished her withering tirade in the same quiet tones and with a positively shrinking demeanor that sent the others into shouts of laughter.

“Say, you’re Janet to a T!” cried Howard. “Her voice is always like that if I happen to hurt her feelings.”

“How about her hair, Howard? Is it long or short?”

“Oh, she wears it bobbed like yours.”

“I suppose,” Dorothy said to Mr. Sanborn, “that you want to smuggle me into the flat and have me change places with her?”

“That’s the idea exactly,” admitted the detective. “And I don’t want you to make your decision until I explain my plan in detail—or, rather, the necessity for the risk you will be taking.”

“Shoot—” said Miss Dixon, “but I can tell you right now, risk or no risk, I’m going through with it. Janet, after all she’s been through and from what Howard has told us, is bound to flop once she gets to Dr. Winn’s. Nervous, and probably high strung, the chances are against her being able to hold up under the strain.”

“I think you are right about that. But although Janet is in serious danger, she could be rescued and her father guarded without bringing you into the picture, Dorothy, if it were not for one thing. These men who hold Janet in their custody are in some way mixed up with Dr. Winn, who has undertaken to make some very important experiments for the United States government.”

“I make a bet that he is Number 1 of the gang!” ventured Bill, the irrepressible.

“Very possibly. That has yet to be discovered. But what I want you young people to realize is that this is no ordinary gang. Quite evidently we are up against an international organization. Their treatment of Janet is concrete evidence of their cold-blooded ruthlessness when they believe their plans to be in jeopardy. If you take your cousin’s place, Dorothy, of course we will see that you are well guarded, but even so, your part in clearing up this mystery will entail a very great element of risk.”

“I’m willing to take the chance.” Dorothy met his inquiring eyes steadily. “Naturally, I’m sorry for Janet and I want to help her. The only thing is, I’ve got to be back at High School by January fourth.”

“I think I can promise you that this job will be cleaned up within a week.”

“I reckon,” smiled Bill, “that you haven’t told us all you know about these lads with numbers instead of names.”

“Not quite all.” Sanborn smiled back at him. “But that is neither here nor there just now. By the way, Dorothy, how are you on shorthand and typewriting?”

“Oh, not so worse. It’s part of the course I’m taking at New Canaan High.”

“Good enough. Frankly, young lady, I would not consider using you, had not the New Canaan Bank robbery, the affair of the Mystery Plane and the Conway Case proved conclusively that you have a decided flair for this kind of thing.”

“Thank you, sir,” said Miss Dixon with mock coyness. “Them kind words is a great comfort to a poor workin’ goil. Do I pack a gat wid me, Mister?”

“You do not. In fact, you will take nothing except what belongs to your cousin. If I am able to get you into the Jordan flat and they carry you up to Ridgefield in her place, just being Janet Jordan, who never woke up when she was sleepwalking last week will be your best protection. Of course, I’m not deserting you. Either I or some of my men will find means of keeping in touch with you constantly.”

“And when the villains scrag me, the secret service boys will arrive on the scene just in time—to identify the deceased! No thank you. If the gun is out of orders, Flash will have to go. Of course my jiu jitsu may help at a pinch, but Flash is more potent and ever so much quicker.”

“What are you talking about, Dorothy?” Ashton Sanborn looked puzzled.

“It’s a cinch you can’t drag a dog along if that’s your big idea,” declared Bill.

“It is not the big idea, old thing.” Dorothy grinned wickedly. “Flash and I have got very clubby this fall. He’s really quite a dear, you know. We travel about together a lot.”

“The mystery of this age,” observed Bill, “is how certain females can talk so much and say so little.”

“Then,” said Dorothy cheerfully, “I’ll let you solve the mystery right now. Catch!” She tossed him a macaroon from a plate on the table. “Go over to that bedroom door,” she commanded. “Stand to one side of the door and throw that thing into the air.”

“But, I say, Dorothy!” interposed Ashton Sanborn. “This is no time for fooling, we’ve got—”

“This is not fooling, you dear old fuss-budget,” she cut in. “It’s—well, it’s just something that may save you from worrying so much about me. Now, Bill, are you ready?”

“Anything to please the ladies,” retorted that young man wearily. He got up and walked to the far end of the room and took his stand beside the closed door. “Is Flash a cake hound? Will he jump for the cookie?”

“He sure will—toss it in the air.”

The small cake went spinning toward the ceiling, and at the same instant Dorothy’s right hand disappeared under the table. With the speed of legerdemain she brought it into view again and her arm shot out suddenly like a signpost across the white cloth. There was a streak of silver light—and the three male members of the quartet stared at the bedroom door in open-mouthed wonder. Quivering in the very center of its upper panel was a small knife, and impaled on the knife’s blade was the macaroon.

“Meet Flash!” said Dorothy.

“Great suffering snakes!” exploded Bill, plucking out the blade, and examining it. “The thing’s a throwing knife.”

“Six inches of razor-keen, leaf-shaped blade,” said Dorothy, “and three inches of carved ivory hilt, beautifully balanced—that’s Flash. How do you like him, fellers?”

“You,” declared Howard, who was still goggle-eyed with surprise, “you are the most amazing girl I’ve ever met, Dorothy!”

“And you don’t know the half of it,” said Bill with unstinted fervor.

“Think I can take care of myself at a pinch, Uncle Sanborn?” Dorothy was laughing at the expression of astonishment on the detective’s face.

“You win, young lady.” He chuckled softly. “After this I’ll keep my worries for Doctor Winn and his friends. Who’d have thought you had anything like that up your sleeve!”

“Not up my sleeve, old dear. A little leather sheath strapped just above my left knee is where Flash came from.”

“Regular Jesse James stuff, eh?” remarked Bill as he handed back the knife.

“Oh, yeah?” Flash disappeared as quickly as he’d come, and Dorothy stood up. “What’s on the boards, now, boss?” she asked sweetly.

“Howard—” said Ashton Sanborn, “will you let me have the key to that apartment of yours? Thanks. Bill and I will need it this afternoon, and even if things go according to Hoyle, we’ll be powerful busy. In the meantime, I’ve got a job for you and Dorothy.” He took out his pocketbook and extracting a sheaf of bills, handed them to the girl.

“You and Howard are going to have a busy afternoon, too. See that you’re back here in time for dinner at seven, and—”

“But what under the sky-blue canopy is all this?” Dorothy was thumbing the bills, counting them. “Why, I’ve never seen so much money—”

“Use it to buy your cousin a trousseau. Have the things sent to Mrs. Howard Bright’s apartment at this hotel. And remember, that when she arrives here, Janet will have nothing but the clothes she is wearing. You don’t mind doing this, do you?”

“Mind! Why, I’ll love it!” Dorothy turned a dazzling smile on Howard, who was simply tongue-tied by the detective’s announcement. “Isn’t he swell, Howard? Isn’t he some guy?”

Ashton Sanborn laughed. “Don’t thank me. Uncle Sam is paying, so you needn’t bring back any change.”

Dorothy thrust the money into her purse. “Don’t worry, old bean, I won’t. So long, you two. Come on, Howard, we’re going to have a beautiful afternoon!” She caught young Bright by the arm and whirled him across the room to the coat-rack. She jammed a bright green beret over her right ear and slung her leopard-cat coat onto her shoulders. “All set for Fifth Avenue!” she called out merrily as she preceded Howard out of the room.