Richard Duvall had had charge of many unusual and intricate cases, in the past, and he prided himself upon the fact that he had handled them with skill and discretion, and that the results which had followed had been both quick and decisive. But in all his career he had not, so far as he could remember, ever felt quite so chagrined, as he did when he threw open the door of the cab and found that the woman he had left there had disappeared.

The fault was his, he knew that well—entirely and unmistakably his. This woman was evidently far more clever, more subtle than he had imagined. He realized now that she had in all probability not taken the drug he had given her in the dressing room of the theater, that she had seen his effort to examine the contents of her handbag, that her weakness, her call for a stimulant of some sort had been but clever acting, and that she had purposely sent him into the drug store in order that she might escape. He blamed himself, utterly and completely, for his amazing stupidity in not realizing that the woman, instead of ordering the cabman to drive away, had only to slip out through the door on the opposite side of the vehicle, and vanish in the darkness.

And this she had quite evidently done. The door of the cab opposite him stood open. No doubt she had purposely refrained from closing it, fearing that the click of the lock might attract the driver\'s attention. The latter with his eyes following Duvall, as the detective entered the store, had remained serenely unconscious of his passenger\'s movements, her clever escape.

At least three or four minutes had elapsed. Duvall glanced up and down the street, but no sight of the vanished woman greeted his anxious gaze. She had had ample time to reach the next corner, and disappear in the darkness. Thoughts of pursuit entered his mind, but he realized at once the fruitlessness of such an attempt. His captive might have fled east or west, at either of the streets north or south of where he stood. Or she might have entered some restaurant, some motion picture house, or other convenient doorway along the Avenue. She might even have boarded a Sixth Avenue car, or hailed a passing cab. He looked up at the chauffeur, who still sat at his steering wheel, totally unaware of the flight of one of his passengers.

"The woman has gone," Duvall exclaimed, nodding toward the vacant cab.

The man turned in complete surprise. He seemed scarcely able to credit the evidence of his senses.

"I—why sir—she was here just a moment ago, sir," he gasped, gazing into the interior of the cab as though he expected its recent occupant to suddenly materialize in the flesh.

"She got out on the other side, while I was in the store," Duvall remarked, shortly, then taking an electric searchlight from his pocket, made a thorough examination of the interior of the cab. He scarcely expected to find anything, although it flashed through his mind that the woman, in her hurry to escape, might have left her bag, her gloves, or something that might afford him a clue to her identity.

At first he saw nothing. Then, as his eyes became more accustomed to the brilliant glare of the electric torch, he observed a bit of white cardboard lying on the floor. It looked like a visiting card, and he snatched it up, devoutly hoping that it had fallen from the woman\'s bag during the attempt he had made to rifle it.

Under the light of his pocket lamp he made a quick examination of his find. It proved a lamentable disappointment. It was in fact a visiting card, or to be more correct, the torn half of one, but what was engraved upon it afforded him not the least clue to either the identity or the address of the woman he sought. On the first line were the words, "Miss Mar"—then came the torn edge of the card. On the second line there was but the figure 1, and then the break.

Was the name so tantalizingly suggested by the letters before him "Miss Mary" something or other? Or "Miss Margaret?" Or was it "Miss Martin," or "Miss Marvin," or "Miss Marbury," or any one of a score of other names beginning with the letters "Mar?" And what was the missing address? What numbers followed the figure 1, on that part of the card that had been torn off? And what was the name of the street? He realized at once that while what he had found might, under certain circumstances, act as a suggestion, it would not serve to get him very far, unless reinforced by other and more definite evidence. He thought for a moment of securing from Mr. Baker a list of the women employees of the studio. It was true, he remembered, that his prisoner had not been seated in that particular section of the house reserved for the company\'s employees, but that might have readily come from the fact that the section was fully occupied when she arrived. Then, as more names beginning with "Mar" occurred to him, the futility of the idea became apparent. Apart from any possible number of Marys, and Margarets there were Martha, Maria, Marcia, Marian, Marcella—others perhaps. Of course he would be able to recognize the woman, if he saw her, but she would be too clever to return to her place in the studio the following day, if by any chance she worked there, knowing, as she must inevitably know, that she would be identified at once.

Still, there was of course the chance that Mr. Baker might have recognized her. He presumably knew all the employees of his company by sight. Duvall got into the cab with a mortifying sense of having made a very foolish blunder, and directed the cabman to drive him back to the Grand Theater.

Mr. Baker was waiting in the lobby when the detective arrived, and at a nod from the latter the two men retired to the dressing room in which they had had their previous consultation. The moving picture man\'s face was eager, expectant, as he waited for Duvall to speak, and the latter felt his chagrin increase by the moment.

When he had at last finished his account of the affair, Mr. Baker looked exceedingly grave.

"Too bad—too bad," he muttered, "to have had her in our hands like that, and then, to lose her."

"Did you ever see the woman before?" Duvall questioned.

"No. Of course she might be in our employ, but I doubt it, although I could not be expected to know by sight every girl who works in the plant. There are stenographers, film cutters and pasters, dozens of others, that I do not engage directly, and never see. Let me look at the card."

Duvall handed the torn bit of pasteboard to him.

"Not much to go on," he said, quietly.

"No. Not much."

"Of course," the detective went on, "the evening has not been entirely wasted. We know the woman by sight, and that is a great deal. As for her name, I have made a careful study of this card, and assuming it to have been of the usual length in comparison to its width, the name following the \'Miss,\' if it was a first name, points to a very short one, such as Mary, and not a long one, such as Margaret."

"How do you make that out?"

"Simply enough. The entire name would of course have been placed in the center of the card, which was, it appears, torn almost exactly in half. On the left-hand side, which we have in our possession, there are, in the word \'Miss,\' four letters, and in \'Mar\' three, or seven in all. We should correspondingly expect to find seven letters on the right or missing half of the card. But were the first name Margaret, or Marcella, which each contain eight letters, or five to be added to the \'Mar\' we already have, it would leave but two letters for the woman\'s last name, and names of that length, or rather shortness, are so rare as to be negligible. It is far more probable that we have but to add a \'y\' to the \'Mar,\' or one letter, leaving six for the last name. This would give us \'Miss Mar-y Gordon,\' with the name evenly divided by the tear. Or, if by chance, the first name is such a one as Marian, containing six letters, we need add but the \'ian,\' or three letters, to the left-hand side of our card, leaving us four letters for the last name. Thus, Miss Marian Kent. The full name on the card should have just fourteen letters, provided the card is, as I conclude, torn exactly in half."

"Why do you conclude that?"

"Because visiting cards of this sort are usually made in standard sizes. I happen to have a woman\'s card—Miss Morton\'s, in fact, in my pocket. Its width is the same as that of the torn card, and if the latter was of the same length, you can readily see that it was torn exactly in half." He took a card from his wallet and laid the torn bit of pasteboard upon it. Their widths were identical. The whole card was just twice the length of the torn one.

"That is a most interesting deduction," Baker exclaimed. "What use can we make of it?"

"I will tell you. You have your car here, have you not?"

"Yes."

"Then I suggest that we run down to the studio at once, get your list of employees, examine the name of every woman upon it, and see if we cannot find one of fourteen letters, including the \'Miss,\' of which the first name begins with \'Mar.\' The chances are that we will be able to locate the name immediately."

"Yes," Mr. Baker exclaimed, rising in some excitement, "but, as you have before said, the woman, if she works for us, will not dare to appear in the morning, for fear that she will be recognized at once."

"That is true, but you will no doubt have on your books her home address. If we hurry, we can get there and back by midnight, and we may be able to place our hands on the woman before she can have time to escape."

Mr. Baker reached the door in two steps.

"Come along," he said. "We\'ll burn up the roads."

The two men said little, during their long ride. When they reached the entrance to the dark and silent studio building, only the night watchman appeared to greet them.

Inside the building, however, there were more signs of life. Some stage carpenters were busy, working overtime on a piece of scenery. In the developing and drying departments were also signs of activity. Mr. Baker led the way to his office. "It happens," he said, "that as I am obliged to O. K. the payroll each week, I have a list of our employees in my desk." As he spoke, he took his keys, opened a drawer, and drew out a small red book.

"Here is the list, with the home addresses," he said. "How shall we go to work?"

"Read me all the women\'s names, in which the first name begins with \'Mar,\'" Duvall said. "I will put them down on a sheet of paper." He drew a pad toward him, took out his pencil, and the two set to work.

When they had at last reached the end of the book, both Duvall and Mr. Baker were surprised to find that the names they had picked out were so few. In all there were but eight, as follows:

Miss Mary Sollenberger,
Miss Mary Green,
Miss Margaret Schwartz,
Miss Maria Rosenheim,
Miss Martha Simmons,
Miss Marcia Ford,
Miss Marian Greenberg,
Miss Mary King.

Duvall ran his pencil down the list of names. "There is but one that fulfills the requirements," he announced. "The sixth name, that of Miss Marcia Ford, contains in all fourteen letters. None of the others do. Two, those of Miss King and Miss Green, come the nearest. Miss King\'s full name contains twelve letters, Miss Green\'s, thirteen. Any one of the three might be the one we seek."

"I can answer for Miss King at once," said Mr. Baker, quietly. "She is my stenographer, and most certainly not the woman who was in the theater to-night."

"That leaves then, Miss Green and Miss Ford. What do they do, and what are their addresses?"

Mr. Baker referred to his book.

"Miss Green is a telephone operator. Her address is given here as 310 Gold Street, Brooklyn. Miss Ford is a film cutter, and lives at 122 West 9th Street, New York."

"Neither sounds particularly promising," Duvall remarked, with a frown.

"No. But of course we are assuming that the woman in question works in the studio. If she does not, our whole fabric falls to pieces." Duvall took the torn piece of card from his pocket and glanced at it.

"The address given here begins with the number 1," he said, significantly. "It may be that Miss Marcia Ford, of 122 West Ninth Street, is the woman we are looking for, although I confess I should have suspected some rival motion picture star, rather than a film cutter."

"By George, I forgot the fact that the card had an address on it," Baker exclaimed. "I think we had better look up Miss Ford at once."

"I agree with you," Duvall said. A few moments later they were driving at top speed back toward New York.

It was five minutes to twelve when th............