"This thing will drive me crazy!" the chief cried. "Flash those torches again! That crook is somewhere right here on the roof! Look for another trapdoor!"
They searched the roof, and found nothing; but again they heard the laugh, only it sounded far away now. Suddenly the roof was bathed in bright light that seemed to come out of the sky.
"He's up there—on something!" the chief shrieked.
They emptied their revolvers and automatics toward the sky. The light died out, flashed forth again and almost blinded them. Once more they heard the sarcastic laugh of the Black Star, as if far in the distance—and then the light was gone.
They stood silent, looking upward. Not the slightest sound came to their ears, except echoes of the shouts in the street below, where people were wondering about the peculiar, blinding light.
"What does it mean?" the chief cried. "Verbeck, what has that devil done?"
"I haven't the faintest idea," Roger Verbeck replied. "I don't understand that laugh, and I can't imagine where that light comes from. I'd think naturally, that it was an airplane, but, as you said, it would be almost impossible to pick a man off the roof at night—and an airplane makes a lot of noise. And we didn't hear a sound—remember that!"
Once more the voice of the Black Star reached their ears. He seemed to be shouting to them, and to be not so very far away.
"Good night, gentlemen!" he called to them. "It has been a splendid evening of amusement and profit. Good night—and let me express the hope that you'll have pleasant dreams!"
That was all. Though they waited on the roof for half an hour longer, they heard nothing more from him, saw nothing of him, and finally they turned and went back down the stairs, puzzled, angry, but determined to make the master rogue pay.