Gintoki and co have launched in the Galactic Merchant Fleet Robot Kaien to take out Dark Vader.  Having made peace with the Renho, they now fight for their pride as Earthlings and samurai against Dark Vader, who has become one with the Renho home planet.  Will they be able to restore peace to the universe?
For the sake of our friends who risked 
their lives for our freedom...
Por el bien de nuestros amigos que arriesgaron sus vidas por nuestra libertad...
Pelos amigos que arriscaram suas 
vidas pela nossa liberdade...