In a world where aliens have invaded Edo Period Japan, skyscrapers, trains and motor bikes have replaced the simple life of Earth inhabitants. One man however, still carries the soul of a samurai, Gintoki Sakata, otherwise known as Yorozuya Gin-san. As reckless as he is, Gintoki carries his own resolve and is ready to take on any challenge with his fellow companions.
While Gintoki Sakata was away, the Yorozuya found themselves a new leader: Kintoki, Gintoki's golden-haired doppelganger. In order to regain his former position, Gintoki will need the help of those around him, a troubling feat when no one can remember him! Between Kintoki and Gintoki, who will claim the throne as the main character?
In addition, Yorozuya make a trip back down to red-light district of Yoshiwara to aid an elderly courtesan in her search for her long-lost lover. Although the district is no longer in chains beneath the earth's surface, the trio soon learn of the tragic backstories of Yoshiwara's inhabitants that still haunt them. With flashback after flashback, this quest has Yorozuya witnessing everlasting love and protecting it as best they can with their hearts and souls.
Aliens known as the Amanto have invaded Earth and taken over feudal Japan. The government has been overpowered and humanity turned into slaves. In this strange new era, a man named Gintoki Sakata with the heart of a samurai, and the odd but endearing company he keeps, have found a way to stay self-employed. They take on all sorts of odd jobs, everything from finding lost kittens to saving the world. Naturally, these odd jobs aren’t always simple, as they frequently have run-ins with police, rebels, and assassins. The jobs rarely go as planned and almost never pay enough to cover their pain—or their rent. But things get really serious when the shogun’s life is in peril, and Gintoki’s past comes back to haunt him. It’s the battle of a lifetime as everyone teams up for a task unlike any other!
Following the grim events of Iga, Kokujou Island, Rakuyou, and multiple fruitless confrontations with the Tenshouin Naraku and Tendoshuu, Gintama. Porori-hen takes its viewers on a trip down memory lane to when Yorozuya were mostly doing what they did best—odd jobs. The great space hunter Umibouzu has returned to Edo and is livid when he finds out that his daughter Kagura has a boyfriend. He blames Gintoki for being an incompetent guardian, but has the time finally come for him to let go of his daughter?
Back with shameless parodies, risqué humor, and lively camaraderie, Gintoki, Kagura, and Shinpachi are faced with unforeseen situations that manage to be both hilarious and emotionally stirring.
Following the temporary retreat of the Altana Liberation Army from the Kabuki District, the state of the war has seemingly improved. However, as the Oniwaban, Shinsengumi, and residents of the district combat the army's remnants, Edo's greatest inventor Gengai Hiraga is abducted. Responsible for causing the enemy's withdrawal by rendering their weapons useless, Gengai's nanomachine virus is now at risk of being shut down.
Meanwhile, a laser capable of obliterating a planet is activated in Earth's orbit on the Liberation Army's mother ship. Another battle ensues when Shinsuke Takasugi and the rest of the Kiheitai arrive on the vessel to stop the weapon from firing. Forced to fight a war on two fronts, the Yorozuya and their allies must prevail on both sides to save Edo and the rest of the world.
