"Oh, no, they weren't," said his neighbor calmly. "Any one can play the game according to the rules if he wants to; there is never any excuse for dirty work." "Germany wants peace with the United States," said the German loudly. "Well, if they do, they take a strange method of showing it," replied the other man with a grim smile. "Personally it's my opinion that we've been patient with Germany far too long. Now they've forced war upon us and for my part I'm ready to go out and fight for my country." Every one in the car was now listening to the discussion, and perhaps the most interested listener of all was young Robert Cook. "Well, I won't fight for the United States!" exclaimed the big German, rising to his feet. "I won't fight for Germany either, but I'll fight all right." He started toward the door of the car, while Bob pondered over his last remark and wondered what it could mean. As the German approached the door, a man dressed in a neat black suit and soft hat got up out of his seat. Bob was watching the German and also noticed this man, though not particularly; he did see that he had a square jaw and a determined look in his gray eyes. The German started to crowd past the stranger who stood squarely in the aisle. "Don't be in such a hurry," said the man quietly. "You stay here." "I want to get off this car," shouted the German angrily. "Get out of my way." "I want you to come with me," said the man still in the same quiet tone. As the German started to protest once more he drew back his coat slightly and Bob saw the gleam of a badge on his coat. "Sit down," he said to the German, who obeyed without further question. There was a mild flurry of excitement in the car, and there were smiles of amusement on the faces of many of the passengers as they glanced at the German sitting meekly in the corner of the seat. He seemed entirely cowed now, and kept his eyes fixed upon the floor, save for an occasional look he stole at the secret service man standing in front of him. The latter seemed entirely at his ease and acted as if not a thing out of the ordinary had taken place. Bob was greatly impressed, and looked with marked respect at the quiet-mannered detective standing near him. He wondered what it was all about, and his father's words of the evening before concerning plotters and spies came again to his mind. He wondered if he could join the secret service and help his country in that way. Then he remembered that he was only seventeen and sighed to think that there was probably less chance of that than there was of being taken into the army. What was the detective going to do with the German, wondered Bob. The car was approaching the high school, and he would have to get off soon and he did not want to miss any of the drama. Suddenly he remembered the police station on the block adjoining the school building and decided that that must be the detective's destination. Bob decided to stay on the car long enough to see anyway.