Gintama: Gintama': Enchousen

Season overview

Role: Meticulous television and film archivist.
Task: Produce a JSON object for "Gintama" Season 6.
Keys: overview (160-220 words), primer (array of exactly 4 concise bullet points).
Constraints: Use only provided synopsis and sources. No invented facts. No markdown/asterisks/headings/bullet points in the prose (though the primer is an array). Output valid JSON only.
Content:
overview: Factual 160-220 word summary of the season's narrative arc.
primer: 4 concise bullet points for previous lore/stakes.
Synopsis:
Gintoki Sakata was away.
Yorozuya got a new leader: Kintoki (Gintoki's golden-haired doppelganger).
Gintoki needs help to regain his position, but no one remembers him.
Conflict: Who will claim the throne as the main character, Kintoki or Gintoki?
Subplot: Yorozuya trip to Yoshiwara (red-light district).
Goal: Aid an elderly courtesan in searching for her long-lost lover.
Setting: Yoshiwara is no longer beneath the earth's surface.
Theme: Tragic backstories of inhabitants, witnessing everlasting love.
Sources:
[1] Gintama (2006) is Animation, Action & Adventure, Sci-Fi & Fantasy. Setting: Aliens invaded Edo Period Japan (skyscrapers, trains, motorbikes).
[2] Wikipedia: Based on Hideaki Sorachi's manga. Produced by Sunrise.
[3] Gintoki Sakata is also known as Yorozuya Gin-san. He carries the soul of a samurai.
[4] Serialized since 2003 (manga). TV series since 2006.
[5] Setting: Aliens invaded and took over feudal Tokyo. Gintoki is an unemployed samurai.
Drafting Overview (Target: 160-220 words):
During Gintoki Sakata's absence, the Yorozuya group finds themselves under the leadership of Kintoki, a golden-haired doppelganger of Gintoki. As Gintoki attempts to reclaim his former position, he faces the significant challenge of having no one remember him. This creates a struggle to determine whether Kintoki or Gintoki will ultimately claim the throne as the main character