A science boy to the core with a superhuman brain, vast knowledge, and a strong spirit of inquiry. He seeks to restore civilization from zero using the power of science in the Stone World, where civilization has ceased. While he has a cool and rational way of thinking, he has a strong passion for his friends. His catchphrase is "This is exhilarating."

A magician and mentalist revived from petrification by Tsukasa. He speaks flippantly in a light, airy tone and manipulates others with his extraordinary speaking skills. He is also skilled at vocal mimicry. He appears in Ishigami Village as Tsukasa's spy, but is gradually drawn to Senku's power to build civilization and becomes an ally of the Kingdom of Science. "Jiima-de," "Goisu," "Doihee."

The scion of the Nanami Conglomerate shipping company, possessing a grand scale and excellent leadership. He boasts outstanding sailing skills and has been handling sailing ships since middle school. He is greedy enough to be called the "greediest man in the world," but also has the side of a stoic hard worker who never compromises on his desires. His trademark is a large captain's hat and a red captain's coat. His catchphrase is "I want it!"

He has an inquisitive, clever, and straightforward personality. He had been collecting various materials to cure Ruri's illness. After meeting Senku, he became fascinated by science and is an ally of the Kingdom of Science, striving to master science together. A science user with flexible ideas who sometimes surprises Senku.

Trusted as the brain of the Kingdom of Science for his extraordinary hearing and insight that allows him to sense danger. Before petrification, he was a Self-Defense Force officer and a submarine sonarman, so he is entrusted as the sonarman of the Perseus. His skill with a bow and arrow is also top-notch.

A girl with blonde hair and blue eyes. A warrior whose light movements and high experience make her a match for any man. She speaks in an archaic manner. She took a liking to Senku's way of life and, after her sister Ruri overcame her illness with sulfa drugs, she lends her strength to Senku as an ally of the Kingdom of Science.

She always wants to be useful to everyone and has a hardworking personality. Though small, she is reliable and excels at infiltration. She can also move by hopping around inside the watermelon shell she wears on her head.

The most skilled craftsman in Ishigami Village, having dedicated 50 years solely to making things. With high crafting ability and a sturdy physique, he is a central figure in manufacturing for the Kingdom of Science, handling difficult crafts single-handedly. When he gets excited, his muscles bulge and his clothes burst off.

A spear user revived from petrification by Tsukasa, he was the de facto number two of the Tsukasa Empire. He handles a special spear called a Kudayari and boasts overwhelming martial might comparable to Tsukasa. He has a cold and ruthless personality, choosing any means to achieve his goals.