ket-headed Earthworm!" said Tom.

The smoke thickened at the moment, and when it cleared again, the great
beast was gone. "I guess the smoke chased him away," said Astro.
"Smoke!" He whirled around. With the threat of the tyrannosaurus gone,
they could face the strange happenings around the clearing.

"Come on," said Tom. He started for the burning buildings in back of the
house.

Just at that moment a group of the green-clad men came around the side
of the house. Astro grabbed Tom by the arm and pulled him back.

"What's going on here? All these ships, buildings burning, and those men
dressed in green. What is it?"

The three boys huddled behind the jet and studied the scene.

"I don't get it," said Tom. "Who are those men? They almost look as if
they're soldiers of some kind, but I don't recognize the uniform."

"Maybe it's the fire department," suggested Roger.

"Wait a minute!" roared Tom suddenly. "There on the porch! Major
Connel!"

"Omigosh!" said Astro. "It is, but what's the matter with him? Why is he
standing there like that?"

"He's been paralo-rayed!" exclaimed Roger. "See how still he is!
Whatever these jokers in uniforms are, they're not friendly!" He raised
his shock rifle. "This last shot in my blaster should--"

"Wait a minute, Roger," said Tom, "don't go off half-cocked. We can't do
much with just three shots. We'd better take over one of these ships.
There must be guns aboard."

"Yeah," said Astro. "How about that big one over there?" He pointed to
the largest of the assembled crafts.

"O.K.," said Tom. "Sneak around this side and make a dash for it."

Gripping their rifles, they slipped around the stern of the small ship,
and keeping a wary eye on the milling men around the front of the
building, they dashed toward the bigger ship.

On the porch of the main house, Major Connel, every muscle in his body
paralyzed, saw the three cadets dart across the field and his heart
skipped a beat. Immediately before him, two of the green-clad men were
holding Sinclair while Hilmarc addressed him arrogantly.

"This is just the beginning, Sinclair. Don't try to cross us again.
Neither you nor anyone else can stop us!" He whirled around and faced
Connel. "And as for you and your Solar Guard, Major Connel, you can
tell them--"

Hilmarc's tirade was suddenly interrupted by a shrill whistle and the
glare of a red flare overhead. There was a chorus of shouts as the men
ducked for cover.

A voice,