“We are looking for evidence that will prove your husband innocent,” Mr. Hugenay told her. “Do you wish us to stop without finding it?”

“Well, no, no, of course not,” Mrs. Smith answered, flustered. “If you can prove he’s innocent, I guess it’s worth any amount of damage.”

“We will try to do no more.” Hugenay made a little bow, and she seemed satisfied.

They had already dug into all the walls looking for a hiding place, so now there was nothing to do but wait. The man named Joe had gone in the car for the tape recorder, and in about an hour he returned, lugging the heavy machine.

“Here it is,” he said. “The old fellow put the tape on, so it’s all ready to roll.”

“Very well,” Hugenay said. He turned to Jupiter, “Do you know how to run this apparatus?” he asked.

“Yes, sir.” Jupiter opened the carrying case of the tape recorder, got out the electric connection, and plugged it in.

“Let’s put the room back the way it was,” he said. “I mean we can’t really do it completely, but let’s hang the pictures and the mirror and put some books back on the shelves.”

Hugenay started to protest, but reconsidered. “Do it, men,” he said, and they obeyed instructions. They rehung the mirror and pictures, arranged some of the books in the bookcases, and stepped back, waiting.

“Now, some action, please!” Hugenay said impatiently. “I think we are wasting time, but let us at least try.”

“Yes, sir.” Jupiter had been running the tape at low volume, listening to it while the men worked. He had located the place on the tape where the scream came, and wound the tape back.

“Now I’m ready,” he said. “Everyone please remain quiet.”

He started the tape and turned up the volume. There were a few words of conversation between a man and woman. Then the scream came, highpitched, desperate, and eerie. It rang through the room, and with a last despairing wail was silent. All of them waited for a secret door to open or a panel to pop out of the wall.

Nothing whatever happened.

“I knew it!” Hugenay exclaimed. “I tell you, boy, there’s no place in this room five valuable pictures could be hidden. No place!”

“I think there is, sir,” Jupiter said, with sudden eagerness. He had noticed something the men hadn’t and suddenly he thought he knew where the stolen pictures were hidden. It only remained to test his theory.

“Let’s try it again,” Jupiter said. “Perhaps the volume wasn’t high enough.”

He pushed the volume knob all the way round. Then he rewound the tape and started the scream once more.

This time it burst upon them as a screech of such terror that they put their hands over their ears. Up, up, up went the sound of the scream until it was almost unbearable.

Then it happened.

The glass in the large mirror on the wall cracked in a thousand pieces. Glass sprayed across the floor. In a second there was nothing left of the mirror but the frame and a few jagged pieces of glass sticking to it.

Where the mirror had been was a brilliantly coloured picture. As they watched, it curled forward and fell to the floor, followed by four more pictures that had been carefully sandwiched between the glass and the frame.

The purpose of the screaming clock was at last explained. Heedless of the broken glass, Hugenay darted forward to snatch up the first picture, an abstract consisting of whirls of colour against a black background.

“The pictures!” he exclaimed in triumph. “Half a million dollars’ worth, and at last I have them!”

At that moment, the library door opened, and a voice behind them said sharply, “Put up your hands! You’re all under arrest!”

There was stunned silence as they all turned and stared at the group of men in the doorway. Two policemen stood with drawn revolvers. Behind them Jupiter recognized Police Chief Reynolds of Rocky Beach, and Mr. Crenshaw, Pete’s father. Then Pete himself squirmed through the group into the room.

“Jupe!” he said anxiously. “Are you all right? Golly, we were worried about you! I couldn’t get to sleep — I wanted to tell you something — so I telephoned your house. Your uncle said you were at Bob’s, and Bob’s mother thought you both were at your house, Jupiter. I called Headquarters, and you weren’t there either. Then I rode over to Headquarters to see if you had left any message. I found your note about the clock room, so I telephoned here, but nobody answered.

“Then I got worried. I told Dad you and Bob were missing and he called Chief Reynolds. We all came here to investigate and it looks like we came just in time.”

Chief Reynolds stepped forward and took the picture which Hugenay was holding. He carefully placed it on the desk.

“This was stolen from a gallery about two years ago,” he said. “I remember, photographs of it were circulated to police at the time.”

He turned to Jupiter.

“I had a hunch this might be serious,” he said. “I remembered about Bob being chased yesterday and something stolen from his car and figured you might be tangling with something big. Looks like we got here just in time to catch the thieves with the stolen goods.”

Jupiter turned and looked at Mr. Hugenay. Considering that the art thief had just been captured after outwitting police for many years, he looked very calm. He was in fact smiling. Now he lowered his hands, took a cigar from his pocket and lit it.

“Tell me, please,” he said, “with what crime am I charged?”

“Well, possession of stolen goods will be enough to start with,” Chief Reynolds snapped. “Then maybe abduction, malicious damage — oh, we’ve got you on a lot of charges.”

“Indeed?” Hugenay puffed on his cigar and blew out a cloud of smoke. “Please do not make reckless accusations, my dear fellow. I came here in a public-spirited hunt for some stolen art treasures that had been hidden by Albert Clock.

“This boy — ” he nodded at Jupiter, “will tell you that he and his friends were aiding me voluntarily with my search.

“The damage to this room was done by permission of the lady in charge of the house. It was necessary to find the stolen paintings. We have found them. We will now turn them over to you, gentlemen, and take our leave.”

“Now wait a minute — ” Chief Reynolds began.

“Tell them I am speaking the exact truth, boy,” Mr. Hugenay requested of Jupiter.

Jupe blinked. It was true, of course, everything Hugenay had said.

“Yes, Chief Reynolds,” Jupiter said reluctantly. “We are here voluntarily and Mr. Hugenay was hunting for the hidden pictures. That’s all absolutely true.”

“But we know all about him. He was going to keep them when he found them!” Chief Reynolds cried.

“That is a matter of opinion,” Hugenay said. “You cannot prove it. So if you will excuse us, we will take our leave now. You will not arrest us, I’m sure, because if you do I will file a suit for a million dollars for false arrest and I will win it.”

He gestured to his men, who were still holding their hands up nervously.

“Come on, men,” he said. “We are no longer needed here. We will say goodnight.”

“Now wait a minute!” one of the policemen exclaimed. “You can’t slip out as easily as all that. We can hold these men for impersonating police officers, anyway!”

“Really?” Mr. Hugenay yawned slightly. “Fred, please step forward. Now, gentlemen, examine the insignia Fred is wearing. Notice the initials.”

“N-Y-P-D!” Chief Reynolds said, puzzled.

“Correct. Standing for New York Police Department. These men are actors, whom I hired to help me in this hunt. They are wearing uniforms of the police department of the City of New York, which is almost three thousand miles away. It is merely a harmless joke on my part. You can’t say that they are impersonating Los Angeles police officers — not when they are wearing New York City police uniforms!”

Jupiter gulped. Now that he looked closely, it was true. Along with everyone else, he had taken it for granted the men were dressed as Los Angeles policemen.