The new anime project was announced back in March 2019
The official Japanese Twitter for the Gintama anime franchise announced today that a new special episode will be streamed on the Japanese streaming service dTV. Its content is related to the upcoming all-new feature film to be released in early 2021.
The post writes:
"Breaking News: Gintama's new special anime episode is in the works!! A big announcement to celebrate the first anniversary of the manga's conclusion! A new anime episode whose content is related to the anime feature film to be released early 2021 is now in the works! It will be streamed on dTV! Stay tuned for further updates!"
Teaser trailer posted in March 2019:
Source: "Gintama" anime official Twitter
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