Illustrations and rhyming text reveal events happening in varied environments, from an icy sea to a blistering desert, while very different things occur down below.

As fourteen-year-old archaeologist Will and his friends plummet down a subterranean pore, they face deadly creatures and discover a strange fungal shelf, which not only reveals artifacts from ancient civilizations, but clues to a lost land at the end of the Earth.

When insane exile Corner and his army of mindless, whispering shadows invade Safe, a secret, underground community of freaks and disabled outcasts, Matthew, traumatized shapeshifter Ariel, and other misfits go to the dangerous place known as Above, where Matthew makes a shocking discovery about the histories entrusted to him.

"When Gran and his family move to Carousel, he has no idea that the town is built atop a secret. Little does he suspect, as he walks his sister to school or casually eats a banana, that mysterious forces lurk mere inches beneath his feet, tearing up the earth like mini-hurricanes and causing the town to slowly but surely sink. When Gran's friend, the difficult-to-impress Catalina Catalan, presses a silver handle into a hillside and opens a doorway...

"Styx and their cohorts of deadly Armagi have swept across England, leaving death and devastation in their wake. Only a miracle can save the day and, in the inner world at the centre of the earth, Will and Elliott might just have stumbled upon one as they uncover ancient secrets that are fundamental to all human and Styx life"--

"It was supposed to just be a normal basement--some storage boxes, dust, you know, the usual basement stuff. But when Milo is sent by his mother to fetch a sock from the basement of the historic home they've moved into, Milo finds a door in the back that he's never seen before. Turns out that the basement of his house is enormous. In fact, there is a whole world down there. As Milo travels ever deeper into the Basement World, he meets the many Things...

"Teenager Eliza and her friends are going to explore a cave near their upstate New York home, but first her friends insist on dragging her to Drowner's Swamp, a bog legendary for its dangerous sinkholes, and a place which her mother has frequently warned her about; Eliza does not want to go, and when the earth opens up and swallows her she finds herself in a system of caves--and what she finds living there is strange and dangerous beyond anything...

As two children and their pet gazelle sneak out of the house in search of treasure, they come across a world beneath the city that is inhabited with monsters and pirates.

Will Burrows believes he is safe at the very center of the earth, in a world that no one knows exists, but the Styx are close behind and will follow him anywhere, while on the surface, Drake and some unlikely allies unearth some critical secrets.

Pat O'Toole, his brother Coop, and their new companion, Kate, have narrowly escaped the cultlike community below New York City but must try to stop the cult's leader, Kate's grandfather.