Spike Spiegel, a bounty Hunter with a dark past, lives on bounty to bounty, barely making it each time, or not making it at all. His partners Jet Black, Faye Valentine, Ed and Ein the dog all help him in his adventures from planet to planet.
Makoto Niwa is a high school boy who, since his parents are away on business, lives with his aunt’s family. It is there he meets his mysterious cousin of the same age Erio Touwa—who happens to tie a futon around her upper body and is a self-proclaimed alien. Her staple food is pizza. Erio had been missing for half a year and was found floating in the sea. She doesn't remember anything about what happened during that period of time, but she began to think that it was the act of an alien and wanders the neighbourhood wrapped in the futon.
Lain Iwakura appears to be an ordinary girl, with almost no experience with computers. Yet the sudden suicide of a schoolmate, and a number of strange occurrences, conspire to pull Lain into the world of the Wired, where she gradually learns that nothing is what it seems to be... not even Lain herself.