y the enormous pressure was gone.

Something was wrong. He hadn't pushed the cut-off button, yet the ship's
engines were suddenly silent. He jabbed at the power switch. Nothing
happened. Then the side-jets sputted, and he was slammed sideways into
the cot.

He snapped on the radio speaker. "Control ... can you hear me?
Something's gone wrong out here...."

"Nothing's wrong," the captain's voice said in his earphones. "Just sit
tight. I'm bringing you back in. There's a call here from Sun Lake City.
They want you down there in a hurry. We'll have to scratch you on this
run."

"_Who_ wants me down there?"

"The U.N. Council office. Signed by Major Briarton himself and I can't
argue with the Major. We're bringing you in."

Greg Hunter sank back, disappointment so thick he could taste it in his
mouth. Sun Lake City! That meant two days at least, one down, one back,
maybe more if connections weren't right. It meant that the captain would
send Morton or one of the others out in his place. It meant....

Suddenly he thought of what else it meant, and a chill ran up his back.

There was only one reason Major Briarton would call him in like this.
Something had happened to Dad.

Greg leaned back in the cot, suddenly tense, as a thousand frightful
possibilities flooded his mind. It could only mean that Dad was in some
kind of trouble.

And if anything had happened to Dad....

* * * * *

The sun was sinking rapidly toward the horizon when the city finally
came into sight in the distance, but try as he would, Tom Hunter could
not urge more than thirty-five miles an hour from the huge lurching
vehicle he was driving.

On an open paved highway the big pillow-wheeled Sloppy Joe would do
sixty in a breeze, but this desert route was far from a paved road.
Inside the pressurized passenger cab, Tom gripped the shock-bars with
one arm and the other leg, and jammed the accelerator to the floor. The
engine coughed, but thirty-five was all it would do.

Through the windshield Tom could see the endless rolling dunes of the
Martian desert stretching to the horizon on every side. They called Mars
the Red Planet, but it was not red when you were close to it. There were
multitudes of colors here ... yellow, orange, brown, gray, occasional
patches of gray-green ... all shifting and changing in the fading
sunlight. Off to the right were the worn-down peaks of the Mesabi II,
one of the long, low mountain