It's only about an hour's walk to the top of the Mammoth Mountains. But no one in the small town of Instep has any intention of ever taking that walk.

They wouldn't dare.

The steepest cliff, the one permanently shrouded in mist, is called Kneeknock Rise. And a horrifying creature lives there.

Not that anyone has actually seen the Megrimum, though some think they have. But everyone can hear its anguished moans and groans on stormy nights, when the rain drives harsh and cold. In terror, the townspeople perform rituals to keep it on its cliff—and away from them.

But Egan is not afraid. He has come to town to visit his relatives during the annual autumn fair. From the moment he arrives, he is intrigued by the tales of the Megrimum. He even has strange dreams about it. As his curiosity grows, so do his fantasies of slaying the creature.

So he climbs to the top of Kneeknock Rise for a close-up look.

Does the Megrimum really exist? What mystery lies behind the mist? Will Egan live to tell what he discovers? Seeing is believing in this Newbery Honor-winning novel.