Markel gave no answer, but went back up the stairs. After a while the door of the workroom banged behind him and soon the roar and rattle of the printing press broke out anew. Frank took a deep breath. "That's the closest call I ever went through," he whispered, in relief. "Let's get out of here. Quick! I'd like to give that cat about a quart of cream for breakfast." They tiptoed quietly out of the room and made their way to the front door of the mill. It was, as Frank had predicted, bolted on the inside, but he drew the bolt and the door swung slowly open. Frank placed his fingers on his lips as a sign for silence. To this Joe nodded understandingly. Then from a distance came an unexpected sound--the mewing of a cat! Both lads had to grin--indeed, it was all Joe could do to keep from laughing outright. They slipped outside, closing the door behind them. "Now to get back to Bayport," whispered Frank. "We'll have to hurry." They sped across the grass toward the borders of the dark wood, and not until they had reached its friendly shade did they look behind. The ghostly old mill stood by the gleaming river, dark and sinister in the clear moonlight. "We'll be back," Joe said, as he glanced back at the mill. "There is going to be a big surprise for that gang before the night is over." "I'll say. Let's get started on it." They ran up through the trees until they reached the deserted road, where they had left their motorcycles. Within a few minutes they were in the saddles and roaring back in the direction of Bayport. They made the journey at full speed, but at that it was late before the gleaming lights of the city came into view. The motorcycles sped down the shore road on to the concrete boulevards, then raced through the city streets, now almost deserted save for an occasional late trolley or nighthawk taxi. At length they drew up before the Hardy home and raced up the front walk. They found their father in the house, sitting up for them. "What on earth kept you out so late? Your mother--" Fenton Hardy began, but Frank interrupted him. "We've found the counterfeiters!" "The what?" demanded Mr. Hardy, in astonishment. "The counterfeiters. Get some men and we can catch the whole crowd this very minute." "Is this right?" asked the detective swiftly. "We've found their plant. We saw them making money. We can bring you there right away. They don't know that we saw them." "And they're getting ready to leave in the morning," put in Joe. "Where are they?" demanded Fenton Hardy. "In the old Turner mill on Willow River. We've just come from there." Mr. Hardy was a man who wasted little time once he had grasped the essentials of a situation. Without a word he hurried over to his study and picked up the telephone. He asked for a number and, after it was secured, he held a brief, curt conversation. Then he put down the telephone and the receiver clicked.