For us. I’m a part of all this now.

Finally I lie in bed, still damp and cool from my shower, and stare at the ceiling, somewhere between happy and sad and drained. My backpack is on the floor beside me. I know I need to go through it soon, take stock . . . but I also know that once I delve into the last thing Mom did for me, the sorrow I’ve kept at bay will return. I will grieve forever, but I know I can’t let myself weep forever.

So I think about this wonderful, strange place I find myself in. Lachlan said there are about two hundred people living here, from infants to elders, all second children. The community has been thriving below ground for around fifty years, ever since a second child rediscovered the hidden world. Even though many of its members venture out into Eden for supplies, it is separate enough that it has developed its own culture.

I haven’t found out exactly what life is like down here, but I can see the difference even in the clothes. In Eden, styles are brash and sharp, deliberately loud and provocative. Here, colors are a little more muted, more natural. The cut is easy, flowing, and often the material is a beautiful patchwork, made up of complementary fabrics interspersed with occasional jarring—but oddly fitting—elements that make the whole outfit extraordinary. The effect of the pieced-together motley somehow isn’t one of patching and make-do, but of a deliberate choice, taking the best of everything and fitting it together into something even better.

Almost everyone I see is wearing a piece of crystal. Most have a simple chunk on a piece of cord around their necks. One pretty young girl has a purple piece at the center of a circlet in her flowing hair. I see one older man with no visible crystal jewelry reach into his pocket and pull out a piece of clear, polished crystal which he rubs meditatively as he talks to me.

I don’t see one on Lachlan, but I notice a thin cord around his neck, braided red and orange in a snake-like pattern. Maybe he has a crystal, too.

I haven’t met anyone beyond Iris and the children, but attitudes here seem so relaxed, so low-key. No one is hurrying to work or entertainment like they do in the inner circles, or hustling in search of money, or away from danger, as they do in the outer circles. People down here seem to operate on a different internal clock. No one seems hunted, harried, like they do up in Eden. Everyone up there, now that I think about it, seems caffeinated, driven, a little too sharp.

Maybe it’s the tree that calms them down, the soothing proximity of nature. Maybe it is a relief to finally be in a place they truly belong.

I start to feel it myself, breathing in the leafy scent, feeling the cool cavern air touch my skin. Eventually, I feel centered enough to go through my backpack.

The first thing I pull out almost makes me lose it: my ragged stuffed chimpanzee. Mom must have rescued him from the garbage and stuck him in the pack when I wasn’t looking. I hug him tight to my chest . . . but then set him gently aside.

There’s one change of clothes, and a pair of soft shoes. A pretty filigree hair ornament Mom often wore. A new sketchbook and a set of pencils.

And, in a tightly sealed bag, a notebook.

Its pages are made from a substance I don’t quite recognize, a plastic of some sort, I think. We use a kind of plastic that is completely recyclable, but I learned in Eco-history that people used to use plastics that couldn’t be easily broken down, that persisted in the environment forever. Plastics choked entire oceans, and the animals that lived in them. I shudder when I touch it . . . though I have to admit that such an enduring substance makes a perfect medium for a book. Waterproof, virtually time-proof, whatever is in here will last through the centuries.

Written in cramped, awkward hand is a manifesto, or maybe a confession. Sometimes the words are perfectly lucid, textbook-clear. In some passages, though, the language rambles incoherently, the handwriting becomes almost illegible, as if the only way the author could squeeze the words out was to scribble them as fast, as unthinkingly, as possible.

I have a sneaking suspicion who the author might be even before I turn to the last written page. The page is at the end . . . and at the middle. That is, the last half of the notebook has been cut out, carved raggedly, hacked, even. The scrunched signature has been added in a different ink on the last remaining page that grips the binding weakly, flapping loosely in the space where the missing pages used to be. I stare at the signature.

Aaron Al-Baz. Prophet of environmental doom. Founder of Eden. Savior of Earth.

And, if these, his own words, are true, a deluded, psychotic monster.

I read through the notebook, and then read it again to be sure I understand. It takes me hours to parse the tale, and when I have, I still can’t believe it. Aaron Al-Baz is a hero, half-god, the whole reason any humans still survive and the only reason the Earth will one day flourish again after the global devastation we caused. Every textbook says so. Every temple hails him as near-divine.

I need to tell someone about what I’ve read, I think at once. But at that very moment there’s a knock on my door and Lachlan walks in without waiting for an answer. I shove the notebook under the bedclothes and force a friendly smile. It must look pained, but he doesn’t say anything. He knows I have plenty to be distraught about.

I need more time to digest what I just read. Society is held together by a common belief. What will happen if that belief is shattered? I have to think. The secret has been kept for more than two hundred years already. It can keep another hour or two.

But I’m numb when Lachlan takes me to meet some of the more prominent members of the Underground. There are cooks, clothiers, musicians, storytellers, healers, and even clergy for the Underground temple. I’ve always wanted to go to a temple meeting. Now everything about the ritual would ring false.

No, not everything. Not the message of hope, the desperate need for us to revive and reconnect with the environment, to love and cherish and respect it.

But as for the focal point of that worship, the man behind it all . . . My lip curls involuntarily. I can hardly pay attention to what I’m doing. I forget to smile, forget names, stand dumb like a post.

Before I’ve met everybody, Lachlan makes my apologies. “She needs rest,” he says, “and peace. We’ll give her time.”

Understanding, the beautiful, happy, mellow people go about their lives. They seem ready to accept me no matter how churlishly I behave.

Lachlan leads me back to the roots of the tree. Some of them snake above the ground before plunging into the Earth. As soon as I get near the tree I feel calmer.