The Champs-ÉlysÉes were blazing with light from the Arch of Triumph to the Place de la Concorde. The cafÉ-chantants were in full blast. Colored electric lights spelled out the names of the different places of amusement. Swarms of cabs and carriages, with their yellow side lamps, came and went. Long rows of tables stood under the trees, surrounded by men and women, who were dining in the open air, bareheaded, chatting, laughing, joyous.

Down the broad avenue went the three American lads, returning to the hotel, where they hoped to find the missing one. The sound of music and singing from the theaters lured them not. The sound of talk, and laughter, and tinkling glasses at the tables did not stop them. The sight of all these people enjoying themselves as human beings can enjoy themselves in no other part of the world did not check their footsteps.

Frank Merriwell had been there before, and he knew all this by heart; but, to Jack and Harry, the sights and sounds were new and novel. At some of the tables, they saw parties of respectable Americans, people of high standing and good breeding, eating and drinking there, beneath the lighted trees at the edge of the sidewalk, utterly unconscious that they were doing anything remarkable. And yet no amount of money could have induced those same persons to sit around a table place at the corner of Thirty-third Street and Broadway, in New York. In Paris, they were ready and glad to adopt the manners of the natives.

Leaving all this behind, the boys hastened to the hotel, where they were again disappointed, for Browning was not there. They looked at each other helplessly.

“Something serious has happened to him,” asserted Frank. “I feel it—I know it!”

“He is to blame for it all!” exploded Jack petulantly. “If he had not taken a nif, and posted off by himself, you’d never run into that joint where you had the scrap. If he’s been knocked down, and robbed, and murdered, he brought it on himself.”

Frank was beginning to feel miserable. He went to his room, where he paced up and down. Then he stole out of the hotel, all by himself, and started back along the route over which he had followed Bruce that morning. Down in the midst of the Elysian Fields he paused, and sat down, all alone, at a table, where he ordered a drink of ginger-ale, and sat sipping it.

Frank had about made up his mind to go to the authorities, and report that the big Yale man was missing. He hated to do it, but he feared he was making a mistake in neglecting to do so. As he sat there, several persons brushed past his table. Who had dropped a slip of paper upon it, he could not tell, but he found it lying there before him.

Merry picked it up. There was writing upon the paper. It said:

“Come to the Theater of the Republic. I will meet you there. I am watching Mart Brattle, and do not wish to leave him.

Frank gave a great jump. He bent over, and examined the writing.

“Browning’s hand!” he exclaimed. “This is from him, but how did it get here?”

There was a mystery. Mysterious happenings were crowding fast.

Frank began to fancy that he understood why Browning had remained away from the hotel all day. The big fellow had been tracking Brattle. Frank sprang up, completely thrown off his guard for the moment. He did not stop to think it over. The Theater of the Republic was near at hand, and soon he was hurrying toward it.

As he approached the entrance, a man suddenly appeared at his side, and grasped his wrist, speaking a single word into his ear:

“Stop!”

Frank faced the man like a flash.

It was Mr. Noname!

“Stop!” commanded the Mystery. “You are going straight to your death!”

Needless to say, Frank stopped.

“You here?” he exclaimed.

“Yes—in time to stop you from falling into the trap. You have been summoned to enter that place. In there, behind a column which you must pass, stands a man with a dagger hidden in his sleeve. He means to place that dagger in your heart!”

Despite himself, Frank shivered.

“How do you know this?”

“How do I know anything? Do not ask me. Have I ever deceived you?”

“Never.”

“I am not deceiving you now. I know whereof I speak.”

“But, my friend, the one I seek has summoned me there.”

“No! The summons was a forgery. Your friend is not there.”

Wondering still more, Frank snatched the scrap of paper from his pocket, and scanned it again, standing there in the glare of lights, which made the place as bright as day.

“It is his writing!” he exclaimed.

“A forgery, I tell you!” persisted Mr. Noname. “A clever one, perhaps; but your friend did not write it. Your deadliest enemy is in there. He is watching the assassin he has hired to do the job. The assassin has laid his plans well, and expects to escape after he has struck you down.”

Frank was convinced, for never had he known the Mystery to tell him anything but the truth.

“What can I do?” he asked.

“Keep away.”

“I can’t do that. You say my enemy is in there? You say Brattle is there, then?”

“Yes; he is there.”

“I want to find him. I wish to shadow him.”

“Better leave him to me.”

“I cannot leave everything to you. My friend Bruce Browning has disappeared. You cannot tell me where to find him.”

“Can’t I?”

“Can you?”

“Perhaps not just now,” admitted the Mystery; “but, if you want to know——”

“I do! I shall not rest till I find out!”

“Then I will help you to find out.”

“I am sure this man Brattle has had a hand in the disappearance of my friend. If not, how does it happen that he knows Browning is not with me? Brattle must be followed—he must be tracked to his hole!”

“Let me do it.”

“You cannot do everything. I must have a disguise. I must go in there! I am determined to go in there!”

“Come with me.”

“Where?”

“I will see that you have what you want.”

They sprang into a cab, the man of mystery spoke to the driver, and away they went. It was not a long drive. The cab dropped them at the door of a dark, little shop. The Mystery knocked with his knuckles against a pane in a window, and soon the door opened. They entered. A coal-oil lamp lighted the place.

“Felix,” said Mr. Noname, “my young friend wants a disguise. It must change his appearance so his best friend will not know him.”

“Oui,” grunted Felix, the withered old keeper of the shop. “I will make him so his own mother could not know him.”

And when Frank issued from the place, less than twenty minutes later, Felix had kept his word. Frank was made up to look like a sap-headed English swell, and his clothes were of the style affected by so many British tourists, who seemed to delight in making themselves as conspicuous and ridiculous as possible. Frank carried a heavy stick, and his hair was combed down over his forehead in a bang. The expression on his face was one of vapid stupidity. He wore a monocle, and he walked in an affected manner.

Thus Frank appeared at the door of the Theater of the Republic, where he paid the price required, and entered. A woman was singing on the stage as Merry came sauntering in. Men were sitting everywhere about the tables, talking to women. No one seemed paying much attention to what was taking place on the stage.

Frank Merriwell looked for the assassin by the pillar—and fancied he found him. A man was loitering near one, his hat pulled over his eyes. This man seemed to scan the face of every person who entered.

“Brattle must be near,” decided Frank.

He took a position where he could watch, and waited to get track of Brattle. The man by the pillar was impatient. It was plain he had about given up. At last, he turned, with an impatient gesture, and declined to remain on the watch longer.

Frank knew well enough that this was one of the ruffians who had attacked him in the saloon. He resolved to try his disguise upon the man.

Approaching the hired assassin, he paused, and drawled:

“Me good fellaw, can yer tell me what houah Anna Held comes on? I have seen the little peach in Hamerica, don’t y’ ’now, and I want to see her hagain, don’t y’ hunderstand. Ya-as, by Jawve!”

The man made a swift and rather savage retort in French, shrugging his shoulders, and turning his back on Merry.

Frank smiled to himself.

“In rather bad temper, I take it,” he thought. “Failed to see anything of your game, and so you are impolite.”

Another man came up hurriedly, and spoke to the one who had been loitering by the pillar. It was Brattle. With boldness, Merry addressed his enemy, his face wearing an expression of idiotic anxiety:

“I say, me deah man, cawn’t yer tell me what time Anna Held comes on? I’d like to see her hagain, ye hunderstand.”

“Oh, go to the devil, you wooden-headed chump!” exclaimed Martin Brattle, grasping his companion by the arm and turning toward the door.

“Haw! Very wude cwecher!” gasped Frank, thrusting the head of his cane into his mouth and staring after them.

He did not let them escape, but when they reached the open air he was following them. It was no easy thing to shadow two men along the brilliantly lighted Champs-ÉlysÉes, but Frank did the job in a manner that would have done credit to a professional detective; and, after a time, they turned into another street, where it was easier.

Frank followed them a long, long time, for they did not seem to suspect that he was at their heels. Then, to his infinite disgust, he lost them. They seemed to melt into the very stones of the street. Frank was certain they must have entered some place near at hand, but he had not seen them do so, and he could not tell which way to turn.

He was thoroughly aroused.

“Well, I’ve done a smart trick!” he muttered. “I’ve let them get away after tracking them here! What would the Mystery say to that?”

“That you did well to track them so far,” murmured a voice, and the Mystery stepped out of a dark doorway within ten feet of him.

The appearance of the strange man gave Frank a start, despite his strong nerves.

“You?” he gasped. “How does it happen that you are here?”

“Do not ask questions now. You wish to know where those men went?”

“Yes.”

“This way.”

Mr. Noname drew Frank in at the doorway. They passed through a narrow passage, ascended a flight of stairs, descended another, and yet another, crossed a cemented cellar, ascended some stone steps, and came out into the little back yard of the cafÉ where the fight had taken place that day. Directly before Frank, beneath the gloomy trees, was the shattered door, now mended and standing in place.

“There is where you will find them,” asserted the Mystery; “but this door is closed now, and it is barred on the other side. Wait. I will pass to the other side and open it for you.”

“How can you do anything like——”

Frank stopped and caught his breath. He was alone! The Mystery had disappeared!

“Well, talk about your modern magic—this beats anything yet! That man comes and goes like a disembodied spirit.”

The Mystery had promised to open that door, and Merry had confidence to believe he would keep his word, so he waited there in the narrow yard beneath the gloomy trees. He heard a distant clock tolling the hour, and the sound gave him a chill, like a bell pealing for the passing of a soul.

Frank pushed against the mended door, but it stood firm before him. He moved about and explored the yard. In this manner it seemed that at least an hour passed. Of course it was not so long, but time dragged slowly with him waiting there. Frank was growing impatient, when he heard a sound behind him, and wheeled about. Black shadows were appearing under the trees. There was more than one of them—there were several! Those shadows moved like creatures of life. They seemed to crouch and steal toward him. In the blackness under the trees there was a whisper. Frank Merriwell recoiled against the mended door, his heart leaping into his mouth.

“Trapped!”

The word leaped to his lips, and his hand flew for a weapon. In that instant those shadows darted forward and sprang upon him. He tried to draw his revolver, but it was knocked from his hand. In falling it was discharged when it struck the ground, and the flash lighted for a single instant the triumphant face of Frank’s enemy, Martin Brattle.

Merry struck hard and sure for that face, and his fist landed. The man was knocked down, but he struggled up, snarling:

“Crush him down! Capture him! Don’t kill him! I have a use for him! Take him alive!”

“If you can!” panted Merry, fighting like a tiger at bay.

They leaped upon him, and he hurled them back. They tried to beat him down, but he stood like iron before their blows. He sent them reeling, cursing, falling. He felt that he had been betrayed at last by the mysterious man who had led him to that spot. A score of times Diamond had warned him that Mr. Noname would turn on him, but he had not heeded the words of the Virginian. Now it had happened. The Man Without a Name had brought him there to that yard and left him in order that he might be captured by Brattle and his gang.

The thought made Frank fight with such fierceness that they could not beat him down. They hurled him against the door time after time, till, at last, it flew open beneath the shock. Frank’s heels caught on the stool, and he fell backward into the passage.

Before he could rise, five men were on him. A light gleamed near and he was dragged farther in. Then he was beaten into non-resistance, and his hands were tied. At last he was a captive in the hands of Martin Brattle!