" Tom looked at his father.

"From another planet," Mr. Swift revealed.

Both boys were amazed and excited. "Wow!" Bud gasped. "Male or female?
Human or animal?"

Mr. Swift's eyes twinkled. "None of those," he replied as the boys
stared, mystified.

CHAPTER II

THE MYSTERIOUS HITCHHIKER

Tom and Bud were bursting with curiosity. Although the Swifts had been
in radio contact with creatures from outer space for many months, this
was the most exciting news yet!

On one occasion, the unknown beings had moved a small asteroid--the
phantom satellite Nestria--into orbit about the earth. Later they had
sent strange samples of the animal life of their planet, aboard orbiting
missiles, to be studied by the Swifts. They had also helped Tom, Bud,
and Mr. Swift a number of times when their lives were at stake while on
daring voyages beyond the earth. What was their latest intention?

The telephone rang and Sandy went to answer it.

"For Pete's sake, Dad," Tom pleaded, "don't keep us in suspense! Who or
what is this visitor?"

Mr. Swift smiled at the boys' baffled expressions. "The fact is that a
message came through today that--"

He was interrupted by Sandy who had come to the door. "The phone call's
for you, Dad. Long distance from Washington."

Bud groaned as Mr. Swift went off to take the call. "It's a conspiracy,"
Bud said. "Everyone's ganging up to keep us from finding out about that
mysterious visitor!"

Tom grinned. "We lasted through an earthquake this afternoon, pal," he
said consolingly. "I guess we can last through a phone call."

Inwardly Tom was as impatient as Bud about the exact nature of the
message.

Several months ago, the space creatures had sent their first
communication in the form of mathematical symbols carved on a black
missile which had landed on the grounds of Swift Enterprises.

Tom and his father had decoded the symbols and beamed out a reply over a
powerful radio transmitter. Later messages had been picked up by radio
telescope and converted to appear as symbols on the oscilloscope screen.

"Sandy must know what it's all about," Bud broke in. "She's the one who
first mentioned the visitor."

"Of course I know," Sandy said mysteriously. "So does Mother and so does
Phyl. But don't think we're going to give it away!" she added teasingly.

Tom and Bud cajoled the two girls and Mrs. Swift for further
information. But Sandy and Phyl only shook their heads, obviously
enjoying t