"Boy! I thought it was all up with us," whispered Joe. "When he came over to open the locker my heart was thumping so loudly I was sure he could hear it."
"Me, too. Well, we can thank their boss—whoever he is. I wonder what kind of place we're in, anyway."
Frank switched on his flashlight.
By its brilliant gleam, he saw that they were in a rocky passageway, a large tunnel evidently in the bluffs along Barmet Bay. It was wide enough to accommodate the roadster, but did not offer a great deal of leeway on either side. It appeared to be a natural tunnel, although there was evidence that human toil had been responsible for widening it and clearing it out.
Frank stepped forward and cast the ray of light before him.
It revealed a blank wall of rock. Then, as he moved the flashlight to one side he saw that the tunnel slanted toward the left.
"What'll we do?" asked Joe. "Follow it up along?"
He spoke in a whisper, but the walls magnified his voice and he awakened uncanny echoes.
"Sure. We'll have to be careful, though, or we might meet them on the way back."
Frank took the lead. He stepped forward very carefully, making no move that might dislodge a loose fragment of rock and start a tumult of echoes that would bring the gang upon them.