Watch Fire Force Season 3 Episode 21 Online

Season 3 Episode 21 — Aired on Mar 7, 2026 • runs about 24 minutes.

Notable cast/guest names in this episode include Gakuto Kajiwara, Yusuke Kobayashi, Saeko Kamijo, Mao Ichimichi.

This page includes 6 official still(s) (when available) plus legal availability links.

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Synopsis

Seeking to settle the score from their last meeting, Arthur challenges Dragon to battle alone. Their fight rages over land, sea, and air. And then, they travel to the surface of the strange moon. In the airless vacuum and extreme cold, Arthur desperately fights back, but then, at last, he collapses. The fate of the world hangs on this battle. Will the Knight King, Arthur, be able to win?

Stills