Rimuru
Tempest is preparing for its longest campaign to date. Bandai Namco
Filmworks officially announced this Friday that the fourth season
of Tensei Shitara Slime Datta Ken (That Time I Got
Reincarnated as a Slime) will premiere in April 2026. What's
most surprising is its broadcast format: the series will run over five
cours (quarters) in total, an unprecedented expanse in modern anime,
starting with two consecutive parts.
Along with
the announcement and a special promotional video, plot details were revealed.
The Jura Tempest Federation celebrates its Founding Festival
and moves diplomatically into the "Human-Monster Co-Prosperity
Sphere". However, success brings new enemies. Factions wary of the
influence of the Demon King Rimuru begin to move.
The main
antagonist will be Granbell Rosso, a former hero and leader of the
Five Elders of the Kingdom of Siltrosso, who together with his
granddaughter Mariabell Rosso, seeks to protect humanity through
absolute control, which will lead them to a direct clash with Rimuru.
Movements
in El Dorado
The
synopsis also teases that the Demon King Leon Cromwell will
begin to perform in the Golden Land with his own goals, while a "new
hero" prepares to awaken.
Production
and Context
Studio 8-Bit returns to animate this massive installment, with Miho Okasaki reprising his role as Rimuru. This announcement comes after the conclusion of the series of light novels, whose final volume (the 23rd) was published on November 29. In addition, fans will be able to enjoy the Tears of the Blue Sea Arc movie, scheduled for February 27, 2026, before the film.
