Episode 24

The Burning Past is the twenty-fourth episode of the Fire Force anime, and the final episode of the first season.

Summary
Vulcan tries hard to make conversation with Shinra, but Shinra is distant and only replies curtly. Vulcan says he knows Shinra has his brother on his mind, but reminds him that he is not alone. He then lightens the mood by telling Shinra not to overthink things, joking that thinking isn't his strong suit. Shinra returns to the 8th.

When Burns took on Shinra, his power is better explained that it is a tremendous amount of heat energy that can boost his physical ability. Burns says he will only tell the truth Shinra if he proves that he isn't weak. Shinra breaks through Burns' force field and lands a hit on his arm. Burns finally agrees to reveal the truth.

Sho's Adolla Burst awakened, and their mother became an Infernal. In that moment, Shinra's abilities manifested. The Evangelist predicted that this would happen. Burns experienced what seems to be an Adolla Link as he witnessed Shinra's mother as an infernal, clutching baby Sho in her arms. Haumea used her electricity to control Shinra's mother from a distance so she could bring Sho to them. In that moment, Burns decided to tell Shinra that his family was dead because of the Adolla Burst being involved.

Shinra realizes that he has seen his mother recently in the world of Adolla. He wants to learn more about it so that he can see his mother again. He assumes this is linked to Captain Hague. Obi agrees that they ought to investigate this. They both propose that if Shinra's mother is still alive as an Infernal, there may be a way to bring her back.