-if we can just
find them----"

"Blind action won't help if we do," said the inspector swiftly. "There
must be all the number of the Brotherhood's members assembled here, and
we can't fight them all."

His eyes suddenly lit and he took the blazing jeweled stars from his
pocket. "These badges! With them we can pose as members of the
Brotherhood, perhaps long enough to find your wife."

"But Chandra Dass will be there, and if he sees us----"

Campbell shrugged. "We'll have to take that chance. It's the only course
open to us."

The current of the inflowing tide was still bearing them smoothly onward
through the winding water-tunnel, around bends and angles where they
scraped the rock, down long straight stretches. Sturt used the motors to
guide them around the turns. Meanwhile, Inspector Campbell and Ennis
quickly ripped from the cutter its police-insignia and covered all
evidences of its being a police craft.

Sturt suddenly snicked off the searchlight. "Light ahead there!" he
exclaimed.

Around the next turn of the water-tunnel showed a gleam of strange, soft
light.

"Careful, now!" cautioned the inspector. "Sturt, whatever we do, you
stay in the cutter. And try to have it ready for a quick getaway, if we
leave it."

Sturt nodded silently. The helmsman's stolid face had become a little
pale, but he showed no sign of losing his courage.

* * * * *

The cutter sped around the next turn of the tunnel and emerged into a
huge, softly lit cavern. Sturt's eyes bulged and Campbell uttered an
exclamation of amazement. For in this mighty water-cavern there floated
in a great mass, scores of sea-going craft, large and small.

All of them were capable of breasting storm and wind, and some were so
large they could barely have entered. There were small yachts, big
motor-cruisers, sea-going launches, cutters larger than their own, and
among them the gray motor-launch of Chandra Dass.

They were massed together here, those with masts having lowered them to
enter, floating and rubbing sides, quite unoccupied. Around the edges of
the water-cavern ran a wide rock ledge. But no living person was visible
and there was no visible source for the soft, strange white light that
filled the astounding place.

"These craft must have come here from all over earth!" Campbell
muttered. "The Brotherhood of the Door has assembled here--we've found
their gathering-place all right."

"But where are they