If you punch links we provide, we may receive compensation.

EW can reveal an exclusive excerpt fromthis second installment, in advance of the books Sept. 12 release date.

Check it out below.

BookCover3Way

Credit: Jesse DeFlorio; Amulet Books (2)

For about the fifteenth time, I checked my seat belt.

But I didnt care about finches or swallows.

An eagle could have chest-bumped my window and it would not have shifted my focus.

The planes engine roared.

I grabbed his shoulder.

His muscles were as solid as rocks and his face was a greenish shade of white.

Is she pulling up?

His mouth barely opened.

I hope so, he mumbled.

A vein on the side of her head pulsed.

She didnt notice me staring back at her.

Was he trying to make us feel better?

If so, he was failing.

Hank leaned over to Ashley.

He held his hand out flat and swooped it up toward the roof of the cockpit.

Should we, you know, ascend?

I thought you knew!

Hawking let go of the controls and waved her hands in a sweeping motion.

She sighed with disappointment.

This is one of yours!

One of my what?

One of your designs!

Hank spun in his seat, scanning the interior.

His mouth was all bunched to one side.

And he was completely stumped.

Only Hank Witherspoon would struggle to recognize one of his own inventions.

Matt reached forward with one of his long arms and pointed.

We couldnt have been more than a few football fields away from the rock wall.

I think hes wondering if were planning to avoid that cliff, I said.

The water was neon blue and smooth as glass.

The thing clearly wasnt a seaplane.

So the only safe choices were up, right, or left.

And if Ashley Hawking didnt pick one of those soon, wed keep heading straight.

No, I wouldnt be the fourth.

That honor would belong to Ashley Hawking.

The world would mourn the loss of the two accomplished adults and my brilliant brother and ingenious sister.

I might be mentioned in the story somewhere, but Im no brainiac.

Maybe a little above, but not by much, and only through effort.

I have to work hard, and read all the time, to keep up with the geniuses.

I told you already.

And not because I think of you as an equal.

She laughed to herself.

I simply prefer the sound of my first name.

Now, honestly, Hank, someone of your intelligence .

I assumed youd see.

Hank was panicking now, his head turning from side to side in jerks, like a broken sprinkler.

she said with excitement.

Is this the underplane?

Ashley fake head-butted the dashboard a few times, then looked up to the ceiling.

The child gets the answer.

Although Ava was relieved, I found this news to be more than a little frightening.

You made a plane out of underwear?

The moment the words escaped I realized Id probably misunderstood.

But no one noticed.

Or at least no one bothered to make fun of me.

Not yet, anyway.

Ava and Matt were pretty skilled at remembering my mistakes, though.

This is the underplane?

His eyebrows rose so high they nearly touched the top of his head.

You actually built it?

Youre right, Jack, she said, swiveling around to look me in the eye.

We are getting awfully close, arent we?

The acknowledgment was nice, but I really wanted her to turn back around.

Would you like to do the honors, Hank?

But it worked beautifully.

Youve only tested it once?

Yes, once, and a thousand times in simulation.

Be confident in your ideas, Hank!

Press the button already.

She pointed to the flashing red number, which just kept dropping.

Three hundred meters is pushing things.

I havent felt this much adrenaline since I climbed Everest.

Matt mumbled something about the cliff.

Ashley had Manga eyes.

I dont know what Ava was thinking or doing.

But this was no time to sit and wait.

Ashley let out a long, almost disappointed breath.

Finally, she said.

Hank had his right hand out, three fingers extended.

He counted down from three.

A moment later, the engine stalled.

The aircraft turned strangely quiet, as if we were suddenly flying in a giant paper plane.

Before anyone could respond, something exploded behind us.

Yet nobody but me panicked.

Ava put her hand on my shoulder.

A rocket-launched parachute, she explained.

That was supposed to happen.

Away from the cliffs.

The lonely floating dock came into view ahead of us.

Out through the window, I noticed two wooden boats rounding the corner of the island.

Matt was staring at his computer screen again, mumbling to himself.

He had a big test coming up, and hed been studying constantly.

One of the downsides of being a genius is that everyone expected you to ace all your tests.

I dont think Hank cared, though.

Matt put more pressure on himself than anyone else did.

But was this really a good time to prepare for an astronomy exam?

So I reached across and closed his laptop.

He didnt protest, which was pretty much a thank-you.

Wow, it works, Ava said.

I told you Id tested it.

Yeah, once, Ava noted.

And a thousand times in simulation, Hank added.

Apparently this was funny.

Normally I avoided asking for an explanation when everyone else understood.

And I hated reminding them that I lived on a lower level of the brain game.

But there were times I needed to know.

What does in simulation mean?

Ashley looked back at me like Id just asked the difference between salt and pepper.

Its a computerized version of reality, Jack, Hank explained.

Its like the difference between Street Racer and an actual street race, with real cars, Ava added.

She knew how to speak my language.

A brown, wide-winged bird swooped in front of us.

Is that a petrel?

Theyre frequent visitors to the island, Ashley said.

Sure, we were finally descending, but the underplane turned about as easily as theTitanic.

As we swung closer to the cliff, I held my breath.

Im not sure anyone even breathed.

Ashley said, her voice more excited than relieved.

So, umm, whats next?

Well, you see, this is the first phase of the transition, Hank said.

Hanks eyebrows arched twice.

Wait and see, he said.

Ava tapped me on the shoulder.

Dont worry, I think youre going to like this.

It is called the underplane, after all.

I still didnt get what boxers or briefs had to do with the five of us landing safely.

But I wasnt about to ask.

So, about that braking chute .

can we use it now?

Not until we slow to thirty miles per hour.

Hank cocked his head to the side, struggling for a view of the parachute suspended above us.

I dont know how to thank you, Ashley.

I never thought anyone would ever build one.

The plane soared through a wide loop.

We were still about the height of a four-story building from the glassy sea.

When Matt was hurt or sick, he didnt want anyone to know.

Hed rather hide off by himself somewhere than let you see him aching.

The two boats came into view again.

They looked like museum pieces.

Ashley Hawking squinted, gagged for a three-count, then breathed in, shook her head, and smiled.

Friends of mine, she said.

As Sun Tzu said, you should treat your enemies as if they are your best friends.

Is he one of those jazz guys, Hank?

Our mentor had strange taste in music, but I was growing to like some of the tunes.

Id been trying to learn their names to impress him.

Ava pointed to the control panel.

Our speed was dropping rapidly.

And we were circling closer and closer to the water.

You used a larger braking chute.

Yes, Ashley said.

In simulation, the chute you suggested didnt slow the plane quickly enough.

Your design was completely inadequate.

Hank paused before answering.

Then we bounced again and again, lower each time, like a stone skipping across the water.

Ava quietly beamed, and my still-green brother relaxed his grip.

When we finally stopped, my heart was thumping.

My hands were cramped.

Apparently, Matt wasnt the only one squeezing the armrests.

I looked out the window.

We had to be a mile away from the shore.

Was this really the right place to land?

And what did all this have to do with underwear?

Ecstatic, Hank pointed to the button on the roof, then asked Ashley, May I?

Youre the guest, Ashley said.

Hank pushed the button with the heel of his hand.

Above me, something clicked.

A thud followed, somewhere behind us.

Then two loud hisses on either side of the plane.

Below me, I heard the sound of rushing water, like a quickly filling toilet bowl.

Suddenly I needed to go to the bathroom, but there were more important things happening.

Glancing out the window, I noticed that the wings were dropping below the surface.

The plane was sinking.

And no one else on board seemed particularly bothered.

This is supposed to happen?

Matt pointed his thumb out the window and swallowed.

Why not shed the wings?

he asked, struggling to get the words out.

The aerodynamic profile of the wings is hydrodynamically efficient, too, Hank answered.

In both cases, youre just moving through a fluid.

Ava put her hand on my shoulder.

She wore several colorful beaded rings.

So I pulled out my new notebook.

Before wed left for Hawaii I had a great idea.

Or a great idea for me, anyway.

That way I wouldnt have to admit it when I wasnt following along.

And sure, I couldve checked on my phone, but then theyd notice.

After a second, I added Sun Somethingunfortunately, Id already forgotten the name of the guy Ashley quoted.

The plane was sinking faster.

But the blue water was already climbing up the sides.

A few seconds later, the underplane dropped below the surface and began gliding down through the blue sea.

Not an aircraft made out of old boxer shorts.

Our ride had transformed into a six-seat submarine.

Id even had some experiences with miniature subs, since my sister had built one.

But Id never been inside an actual submarine.

On the one-to-ten scale of soul-stretching, brain-twisting experiences, Id give this one a fourteen.

The water was filled with specks that sparkled in the sunlight.

A group of long silver fish darted past our windows.

Id always imagined that riding in a submarine would be like staring at the fish tanks in an aquarium.

But now it felt as if we were the ones trapped in the tank.

And I kind of wanted to get back to the air.

So that was fun, I said, but can we go back up now?

Of course not, Ashley said.

The underplane nosed down in the direction of the island.

But we werent going to Nihoa.

Far below us, an enormous, brightly lit underwater building hung below the dock.

It looked like the headquarters of some kind of powerful secret society or nefarious villain.

The outside was swarming with huge fish.

You still want to go back up, Jack?

I could practically hear her smiling.

No, I said with a grin.