In the year 2010 AD, Hyper Hurricanes born concurrently all over the world caused severe damage. Five billion people lost their lives, decreasing the world's population to 3 billion. Existing economies and military were wiped out. Countries were frozen under solid ice, plains sank beneath seas, the world was changed dramatically. Human civilization enters a chaotic era. Poverty flourished outside of these economic zones and slums were widespread. The ruling class called themselves Logos and maintained their position by force of arms. They call the poor Revenus, who are exiled to live outside the special economic areas. Time has passed since then. Katsuragi Jo and Tsurasawa Jin, escape from Phantom, a force organized to watch Revenus and to suppress renegade elements of the Logos, taking with them a mysterious girl, Nobuto Sana. There are many who are interested in her, all with their own reasons.

In California's Center City, shy but kindhearted Joseph Carter "Joey" Jones lives with his grandmother, working in a coffee shop. Though his family is financially burdened and he is bullied at school, he remains cheerful. A robotics enthusiast, he wants a top-of-the-line toy robot called a Heybo more than anything. One day Joey and his friend Simon "Psy" Kaina come across a destroyed Heybo discarded by a group of rich kids. He takes it home and repairs it himself, excitedly naming it Heroman. However, one night Heroman is struck by lightning and comes to life, growing several times its size in the process. That same night Center City is attacked by aliens called Skrugg whose attention was brought to Earth after Joey's acquaintance Professor Matthew Denton made attempts to contact them. Along with Joey, Heroman quickly heads to the scene of the attack, where he finds people in trouble, including his friend Lina Davis and her father. Using an arm-mounted controller, Joey is able to command Heroman to use superpowers to fight off the Skrugg and rescue civilians. As the aliens continue their invasion of Earth, the duo are the only ones separating humanity and destruction. [Written by MAL Rewrite]

A special animated commercial to celebrate the release of the manga's fifth volume. The full length version of the commercial was released on Kodansha's official YouTube channel the day after the short version was released on TV. It features the anthropomorphized cells of a human body, with the protagonist being a red blood cell named AE-3803.

The story follows Benio "Haikara-san" Hanamura, who lost her mother when she was very young and has been raised by her father, a high-ranking official in the Japanese army. As a result, she has grown into a tomboy. Contrary to traditional Japanese notions of femininity, she studies kendo, drinks sake, dresses in often outlandish-looking Western fashions instead of the traditional kimono, and is not as interested in housework as she is in literature. She also rejects the idea of arranged marriages and believes in a woman's right to a career and to marry for love. (Source: ANN)