an't imagine how this crook
who signs himself Doctor Satan found it out."

_4. The Shell_

The house was serene and beautiful on the bay shore. The sun beat back
from its white walls, and glanced in at the windows of the rear terrace.
It shone on a grotesque figure there; a man with the torso of a giant,
but with no legs--a figure that hitched itself along on the backs of
calloused hands, using muscular arms as a means of locomotion.

But this figure was not as bizarre as the one to be found within the
house, behind shades drawn to keep out any prying eyes.

Here, in a dim room identifiable as a library, a tall man stood beside a
flat-topped desk. But all that could be told of the figure was that it
was male. For it was cloaked from heels to head in a red mantle. The
hands were covered by red rubber gloves. The face was concealed by a red
mask, and over the head was drawn a red skull-cap with two small
projections in mocking imitation of Lucifer's horns.

Doctor Satan!

In the red-gloved hands was a woman's gold-link purse. Doctor Satan
opened it. From the purse he drew a thing that defied analysis and
almost defied description.

It was of metal. It seemed to be a model in gleaming steel of a problem
in solid geometry: it was an angular small cage, an inch wide by perhaps
three and a half inches square. That is, at first it seemed square. But
a closer look revealed that no two corresponding sides of the little
cage were quite parallel. Each angle, each line was subtly different.

Doctor Satan pointed it at the library wall. The end he pointed was a
trifle wider than the end heeled in the palm of his hand. On this wider
end was one bar that was fastened only at one end. The red-covered
fingers moved this bar experimentally, slowly, so that it formed a
slightly altered angle with the sides....

The library wall was mist, then nothingness. The street outside was not
a street. A barren plain stood there, strewn with rocky shale, like a
landscape on the moon.

The little bar was moved back, and the library wall was once more in
place. A chuckle came from the red-masked lips; a sound that would have
made a hearer shiver a little. Then it changed to a snarl.

"Perfect! But again Ascott Keane interferes. This time I've got to
succeed in removing him. An exploded heart...."

He put the mysterious small cage back in the gold-link purse, and opened
the desk drawer. From it he took a business letterhead. It wa