The story takes place in Edo, Japan, which has been taken over
by aliens (Amanto). The samurai of Japan have all fallen since the
Amanto placed a ban on carrying swords in public. The story focuses
on an insane samurai with a natural perm, Sakata Gintoki, his
(partial) apprentice who he framed in the first chapter, Shimura
Shinpachi, and a teenage girl from the "Yato" clan, Kagura. All are
"freelancers" who search for work in order to pay the monthly rent,
which usually goes unpaid anyway.
tomorrow i go buy the comic oso. 
Official Site: http://annex.s-manga.net/gintama/main.html
