be
trained upon the other side of that door by the aliens. They might be
walking into a trap.

He half expected one of those disconcerting thought answers from
Dalgard. But the scout was playing safe--nothing must upset the
stranger. Confronted by what had to be done, he might be influenced
into acting for them. So Dalgard strode softly ahead, apparently not
interested in Raf.

One of the mermen worked at the door, using the point of his spear as
a lever. Here again was a vista of machinery. But these machines were
alive; a faint hum came from their casings. The mermen scattered,
taking cover, a move copied by the two humans.

The pilot remained in hiding, but he saw one of the furred people
running on as light-footedly as a shadow. Then his arm drew back, and
he cast his spear. Raf fancied he could hear a faint whistle as the
weapon cut the air. There was a cry, and the merman ran on, vanishing
into the shadows, to return a second or two later wiping stains from
his weapon. Out of their places of concealment, his fellows gathered
about him. And the humans followed.

Now they were fronted by a ramp leading up, and the mermen took it
quickly, their bare, scaled feet setting up a whispering echo which
was drowned by the clop of Raf's boots. Once more the party was alert,
ready for trouble, and taking his cue from them, he kept his stun gun
in his hand.

But the maneuver at the head of the ramp surprised him. For, though he
had heard no signal, all the party but one plastered their bodies back
against the wall, Dalgard pulling Raf into position beside him, the
scout's muscular bare arm pinning the pilot into a narrow space. One
merman stood at the crack of the door at the top of the ramp. He
pushed the barrier open and crept in.

Meanwhile those who waited poised their spears, all aimed at that
door. Raf fingered the button on his gun to "spray" as he had when he
had faced the attack of the scavengers in the arena tunnels.

There was a cry, a shout with a summons in it. And the venturesome
merman thudded back through the door. But he was not alone. Two of the
black guardsmen, their flamers spitting fiery death, ran behind him,
and the curling lash of one of those flames almost wreathed the runner
before he swung aside. Raf fired without consciously aiming. Both of
the sentries fell forward, to slide limply down the ramp.

Then Dalgard pulled him on. "The way is open," he said. "This is it!"
There was an excited