um. "Finish your supper while I lock
the back door."

"Don't forget to set out the milk bottle before you barricade us in,"
Susan laughed.

Penny picked the bottle up from the kitchen table and crossed the porch
to place it on the step. It took her so long outside that Susan came
to the door to learn what detained her. She was astonished to behold
Penny standing as rigid as a statue, her eyes riveted upon the garage
door.

"What's wrong?" Susan inquired.

"Didn't I close that door when I put the car away?" Penny demanded in a
low tone.

"Why, yes, I'm sure you did. The wind must have blown it open."

Penny shook her head.

"The door has a special catch so I know it couldn't have opened by
itself. Susan, I believe someone has sneaked into the garage since we
left it!"

Susan's eyes dilated with fear. Involuntarily, she took a step
backwards, turning toward the kitchen door.

Penny caught her by the hand.

"Don't tell Mrs. Gallup or she'll go into hysterics. Let's find out if
there really is anyone in the garage before we call the police."

At first Susan hung back, but when she found that Penny was determined
to investigate the garage alone, she reluctantly followed her chum down
the path.

Cautiously, they peeped into the garage. It appeared to be deserted.

"I'll get Dad's flashlight from the sedan pocket," Penny whispered.

She tiptoed across the cement floor. Groping about inside the car she
found the light, but before she could turn it on she was startled to
hear a slight sound overhead.

Penny's heart began to beat a trifle faster. She was almost certain
that someone was hiding in the little room above the garage. In former
years it had been occupied by a chauffeur whom Mr. Nichols employed,
but now that the detective drove his own car it was used only for the
storage of a few old boxes and trunks.

"Don't you dare go up there!" Susan whispered tensely, sensing the
thought in her chum's mind. "It isn't safe."

"It's safe enough if you stand guard here at the door," Penny insisted.
"If anything goes wrong scream for Mrs. Gallup."

Before Susan could stop her she tiptoed across the cement floor and
quietly crept up the stairway leading to the storage room.

Reaching the top step Penny paused to listen. She could hear no
unusual sound, yet a certain intuition warned her that someone was in
the room.

Systematically, she flashed the beam of her light over the walls.
Nothing appe