as already running
toward the combatants. Blake was glad at the prospect of an ally.
Zehru's dazed condition was swiftly passing. He had now stopped his
retreat and was already fumbling a tentacle toward the tube-weapon in
his belt.

Blake flung himself upon Zehru in another effort to beat him down before
he could draw that weapon, but his metal club glanced harmlessly off the
tentacles Zehru raised to shield his head. Then beyond Zehru Blake saw
something that made him stop his assault.

* * * * *

It was Mapes, sprinting toward the silver arch-gate at the other end of
the enclosure. Blake's heart sank as he realized the gangster's
treachery. If he once reached that arch he could send himself safely
hurtling back to Earth, while Blake and Helen would be left to perish
with Zehru in the explosion that would immediately follow. It was too
late for Blake to head the gangster off. He had already covered half the
distance to the arch.

Zehru noted Mapes' fleeing figure almost as quickly as did Blake.
Swiftly the Xollarian swung his tube-weapon into line with the fleeing
gangster. A thin pencil of dull yellow light of a peculiar density
spurted from the tube toward Mapes. There was a flash of blinding flame
as the light beam met the gangster's body; then Mapes' figure seemed to
literally explode, as though blasted by dynamite from within. So
devastating was the force of that explosion that nothing remained of
Mapes' body beyond a few scattered fragments of shoes and clothing.

Blake was still dazed at the cataclysmic suddenness of Mapes' death as
Zehru swung the tube around to train it upon him. Only a last-minute
desperate effort upon Blake's part saved him. His wildly thrown metal
club made a lucky hit on the tube itself, knocking it, shattered and
useless, out of Zehru's grasp.

Unarmed, Zehru faced Blake with his face contorting in agony. For a
moment the Xollarian swayed there, apparently trying to gather his
failing strength for the next move. The deadly air of the enclosure was
already taking hideous toll. The scaly flesh of his head and face was
dissolving like melting butter.

Zehru's strength was ebbing too swiftly for him to have any chance of
gaining safety through either of the distant side walls. His only hope
of fighting back to the purple mists was to pass Blake and go through
the nearby end wall through which he had originally been drawn.

He came lunging forward in a