Professor
Paws von volt
Geronimo Stilton
My dear mouse friends,
Have I ever told you how much I love science
fiction? I’ve always wanted to write incredible
adventures set in another dimension, but I’ve never
believed that parallel universes exist . . . until now!
That’s because my good friend Professor Paws
von Volt, the brilliant, secretive scientist, has
just made an incredible discovery. Thanks to some
mousetropic calculations, he determined that there
are many different dimensions in time and space,
where anything could be possible.
The professor’s work inspired me to write this
science fiction adventure in which my
family and I travel through space
in search of new worlds.
We’re a fabumouse crew:
the spacemice!
I hope you enjoy this
intergalactic adventure!
Grandfather
william
stiltonix
robotix
benjamin
stiltonix
and
buGsy
wuGsy
traP
stiltonix
thea
stiltonix
Geronimo
stiltonix
Scholastic Inc.
The
underwaTer
planeT
Copyright © 2014 by Edizioni Piemme S.p.A., Palazzo Mondadori, Via
Mondadori 1, 20090 Segrate, Italy. International Rights © Atlantyca
S.p.A. English translation © 2016 by Atlantyca S.p.A.
The publisher does not have any control over and does not assume any
responsibility for author or third-party websites or their content.
GERONIMO STILTON names, characters, and related indicia are copy-
right, trademark, and exclusive license of Atlantyca S.p.A. All rights
reserved. The moral right of the author has been asserted.
Based on an original idea by Elisabetta Dami. www.geronimostilton.com
Published by Scholastic Inc., Publishers since 1920, 557 Broadway, New
York, NY 10012. SCHOLASTIC and associated logos are trademarks
and/or registered trademarks of Scholastic Inc.
Stilton is the name of a famous English cheese. It is a registered trade-
mark of the Stilton Cheese Makers’ Association. For more information,
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www.atlantyca.com.
This book is a work of fiction. Names, characters, places, and incidents
are either the product of the author’s imagination or are used fictitiously,
and any resemblance to actual persons, living or dead, business estab-
lishments, events, or locales is entirely coincidental.
e-ISBN 978-0-545-87527-1
Text by Geronimo Stilton
Original title Il mistero del pianeta sommerso
Cover by Flavio Ferron
Illustrations by Giuseppe Facciotto (design) and Daniele Verzini (color)
Graphics by Marta Lorini
Special thanks to AnnMarie Anderson
Translated by Anna Pizzelli
Interior design by Kevin Callahan / BNGO Books
First printing 2016
In the darkness of the farthest galaxy in
time and space is a spaceship inhabited
exclusively by mice.
This fabumouse vessel is called the
MouseStar 1, and I am its captain!
I am Geronimo Stiltonix
, a somewhat
accident-prone mouse who (to tell you
the truth) would rather be writing novels
than steering a spaceship.
But for now, my adventurous
family and I are busy
traveling around the universe
on exciting intergalactic missions.
This is The
laTesT advenTure
of The spacemice!
a rare day off!
It all started
early
one morning. I woke
up feeling
fabumouse
! Of course I
would have loved to stay in bed for another
hour or two. In fact, given the chance,
I would
snuggle
under the covers until
midday!
But I was up earlier than usual for a good
reason. Oh, I’m so sorry! I almost forgot
to introduce myself! My name is Stiltonix,
Geronimo
Stiltonix
, and I’m the captain
of the MouseStar 1, the most mouserific
spaceship in the universe. (Honestly, though,
my secret dream is to be a
world-famouse
writer!)
As I was saying, I had asked my
personal
assistant robot
, Assistatrix, to wake me up
early that morning. I was planning to enjoy
space beach
. Even the captain deserves
a little rest and relaxation every once in a
while, don’t you think?
So I put on my
bathing
suit
instead of my captain’s uniform, and I
double-checked my bag to be sure I had all
the
essentials
. . .
Massaging
flip-flops
Sun-shading hat
Self-drying
towel
Snorkeling
mask
Floating beach umbrella
Massaging
flip-flops . . .
check!
Sun-shading
hat
. . . here!
Self-drying towel . . . got it!
Snorkeling
mask . . . there it is!
Floating
beach umbrella . . .
yep!
Digital
sunglasses
. . .
hmmm . . . where were they?
I couldn’t find them anywhere!
Where could they be?
Oh yes,
how embarrassing!
They were right on
top of my head!
I was ready to go.
“Beach, here I come!” I cried
happily. Then I opened my cabin
door and . . .
bang!
I bumped right into my cousin Trap.
“Wow, Cousin!” he said in
surprise
.
“What are you doing up so early?”
&nbs
p; “N-nothing special,” I mumbled quickly.
Trap gave me a look. “Oh, really?” he said
skeptically. “Then why are you
DRESSED
like that?”
“W-well, I w-was . . .” I stuttered.
My cousin pulled one of my
flip-
flops
out from the top of my bag.
E
r
.
.
.
“Don’t tell me you’re going to the beach
without
inviting
any of your family or
friends?!” he said.
Black
holey
galaxies
, he had
figured it out! Now what was I going to do?
Don’t get me wrong: I really
love
my cousin.
But I had been looking forward to
relaxing
on the beach all by myself. I wanted to focus
on the new
book
I was writing. With Trap
there, I would be forced to play one beach
game after another! Sigh.
“Er
.
.
.
yes, that’s where I’m going,” I
confessed. What can I say? I’m an
honest
mouse!
“I knew it!” Trap said
triumphantly
.
“But you’ll be so
bored
there by
yourself. You know what? I’ll get my things
and come with you!”
to the beach,
everyone!
Benjamin!
Hi, Uncle!
In the end, Trap was right: A day at the beach
is a lot more
fun
with good company! So
I
called
my nephew Benjamin; his friend
Bugsy Wugsy; and my
sister
, Thea.
When we went by to pick them up, they
were all ready to go.
“
Hi,
Uncle!
” my sweet
jumped into my arms and
gave me an
enormouse
hug.
“Thanks for inviting us to go
to the beach with you!”
“You’re welcome!” I said.
“Now we’re all here.
Let’s
go!
”
“Not so fast, Cheesebrain,” a loud voice
called. “You weren’t thinking of going to the
beach without me, were you?”
It was my grandfather,
William
Stiltonix
,
MouseStar 1’s retired admiral (and the
former captain of the ship!).
“H-hello, Grandfather,” I stuttered. “I-I
thought you hated the beach. You know, the
SUN
, the space sand
—”
“Well, you thought
wrong
!” Grandfather
interrupted me. “Everyone knows
the
ocean
air is good for a
mouse my age!”
So we all
squeezed
into
an astrotaxi and sped off
toward
MouseStar 1’s very
own space beach.
I know it sounds
impossible
, dear reader,
but it’s true! The lower part of our spaceship
is a natural biosphere that contains various
habitats: There are very
tall
mountains,
rainforests
, lakes, and a wide beach
with golden sand by a
crystal-clear
ocean!
“It’s so beautiful here!” Thea exclaimed
when we arrived at the beach.
“You had an
excellent
idea this
time, Cuz,” Trap proclaimed.
“Yes, an excellent idea, Captain,” said a
voice behind me.
I turned around to see
Sally
de
Wrench
,
MouseStar 1’s expert in photon circuitry,
hyperspace engines, and stellar energy.
In other words, she’s our ship’s technical
genius
! And she also happens to be the
loveliest
rodent in the entire galaxy.
“I hope I’m not
intruding
,” Sally
continued. “Thea told me you were coming
How
nice!
From the Encyclopedia Galactica
Natural biosphere
This area of the
MouseStar 1
includes
various natural habitats, including an ocean,
mountains, a desert, and a lake. It’s an ideal
place for a fabumouse space vacation!
Catch!
to the beach, so I thought I’d join in the
fun.”
“No, no,” I told Sally, turning as
red
as a
space tomato. “It’s absolutely no bother at
all. It’s a
pleasure
to have you with us!”
“Okay, okay, enough talking!” Trap
interrupted us. He was dressed from snout
to tail in
swimming
gear, complete with
a mask and fins. “Everybody in the ocean!”
Then he grabbed my paw and pulled
me toward the water.
a mysterious
object
As you’ve probably figured out by now, I
love
the beach. There’s nothing better than
warm sand under my
paws
and the sun on
my
fur
while I clutch a cheese shake with
a
floating
umbrella in one paw.
Ahhhh!
While I enjoy taking a gentle dip in the
ocean to
cool
off, though, there’s one thing
that’s definitely
not
for me:
diving
!
But thanks to my cousin Trap, I found myself
at the top of a cliff with the ocean
far
,
far
,
far
below me.
“Come on!
Jump!
” Trap said, prodding
me from behind.
Sally was
watching
us from the beach. I
Jump!
didn’t want to make
a fool of myself.
I leaned out a bit to
look at the
sparkling
water. Suddenly, Trap
gave me a shove! I
flew clumsily off
the cliff, belly
flopping into the
ocean below.
Splash!
how embarrassing
!
When I got out of the
water
Trap
was busy making fun of me.
“What a flop, Cousin,” he teased.
“Diving is definitely not your
forte
! Let’s
play some Frisbix instead.”
“
Good idea
,” I replied, hoping to make
up for my superstellar flop.
But the game turned out to be harder than I
thought
. I tried to throw the
Frisbix
disk along the programmed trajectories, but
it kept bouncing off course, flipping around
by itself, and getting
stuck
in the sand!
“Hmm,” Trap said teasingly. “Maybe
Frisbix isn’t your forte, either. Maybe you
should go help the mouselings build a
sand
spaceship
!”
From the Encyclopedia Galactica
Frisbix
Frisbix is a favorite game of spacemice
at the beach or park. To play, mice throw an indestructible
disk made of stellar steel along various trajectories
programmed into it. The momentum created by the
player’s throw determines where and how far the
disk flies.
Help!
I ignored my
cousin and tried throwing the disk
again with all my strength.
Wooooosh!
Galactic Gorgonzola! I had flung the
disk so hard I was sure it would stay on
course now.
“See!” I shouted proudly. “Look how
fast
that disk is flying!”
Hey, wait a minute
—
the disk wasn’t
stopping
!
It soared over Trap’s head, past
Grandfather William (who was sleeping in
the
sun
), and landed right in the sand
spaceship that Benjamin and Bugsy Wugsy
had just finished building.
What a disaster!
I ran over to the mouselings to apologize.
But before I could utter a word, an ear-
piercing scream made my
fur
stand
on end.
“Ouuuuchhhh!”
When he’d ducked out of the way of the
flying
Frisbix disk, Trap had stubbed his
paw on something in the sand. Sally dug it
up to see what it was: a perfectly
smooth
sphere.
“Hmmm,” Sally said as she studied the
object, a
puzzled
expression on her snout.
“This looks like an
alien
object. I’m not
familiar with this
material
. . .”
“Well, why don’t we put it aside so nobody
else gets
hurt
?” I suggested.
“Ahem.” Thea cleared