In Smallville, young Clark Kent recalled the many adventures he had been having. On top of those (as Superboy) and his school life (as Clark Kent), he had not had a chance to revisit any of the wondrous places that he had seen. He had been to other planets, even other solar systems, to the bottom of the ocean, into the past, into the future, and even to the earth’s core. That particular journey to the earth’s core had been one of his contributions to science, but he’d never followed it up, having been called upon to save people from some form of crystal creature which had emerged from inside the earth in search of its missing baby.

It would be nice to explore whatever territory lay beneath the earth’s surface again, Clark considered. He waited until he had a Sunday morning to himself, while Lana Lang was busy with her archeologist father, and then stripped off his Clark Kent clothes and glasses, quickly pushed a wavy part of his hair down over his forehead in the shape of an S curl, and flew off the Kent property at super speed, so that nobody would see Superboy leaving Jonathan Kent’s home.

In little time, he was joined by his playful Superdog Krypto. Superboy chose an isolated spot, where nobody would be likely to follow, and then began whirling his arms like a helicopter, while his body ploughed into the earth, carving a wide tunnel.

He was expecting to have to dig for a long time in order to get anywhere, but he was only fifty feet down, when he came out in a cavern which was lit by glowing underground rock formations. Superboy and Krypto followed the caverns for hours at super speed, sometimes running, sometimes flying. They came out in all sorts of underground lands, observed many hitherto undiscovered civilizations, storing everything they saw in their super memories in only moments.

Then, to their even greater surprise, they came upon the sight of two men in combat with a party of four other people on the edge of a cliff. The most brutish of the two men was holding a large rock above his head, about to throw it at their four victims, who were backing towards the edge of the cliff side.

“Those people need help, Krypto,” said Superboy, “You stop that boulder, while I rescue the people.”

Superboy and Krypto flew onto the scene. Krypto charged at the boulder and knocked it over the man’s head, out of his grip and onto the ground behind him. Superboy came in from the open space in front of the cliff, and quickly wrapped his arms around the huddled frightened four people and lifted them out of harm’s way and set them down a few meters behind the fallen rock.

“Thank you, whoever you are,” said the man who seemed to be the leader of the group, “I’m Professor Lindenbrook. This is my guide Lars, his duck Gertrude, my niece Cindy, and Alec, a student. Those two are Count Sachnussem and Torg. They caused an explosion, which trapped us underground. We’ve been on our way to the center of the earth, to try to learn of another way to the surface. You’re the most powerful beings we’ve met down here.”