Muscle Heat

In 2009, CPO Joe Jinno, a former U.S. Navy SEAL, is shown sitting in a military jail cell in Roanoke, Virginia. He was court-martialed for refusing to kill terrorists, as he disapproved of killing scared children, which led to his situation. The scene sets the tone for Jinno's background as someone driven by a strong moral code.

Japanese detective Aguri Katsuragi secures amnesty for Jinno, and two months later, Jinno joins an undercover mission. Their goal is to stop the circulation of Blood Heat, a powerful new drug that acts as a super steroid, circulating through underground channels. The mission is initiated by the U.S. Secretary of Defense.

Jinno and Katsuragi discover that Lai Kenjin is the mastermind behind Blood Heat and operates the Muscle Dome, an underground fight ring. The champion, Lee Son-Min, uses Blood Heat to demolish opponents, exemplifying the drug's dangerous effects. The scene highlights the sinister operations surrounding Blood Heat.

Jinno and Katsuragi intervene at a nightclub where a deal between Kenjin and Russian drug dealers is about to happen. They succeed in preventing the deal but fail to catch Kenjin, who escapes. During the chaos, Katsuragi is kidnapped, escalating the stakes of their mission.

Katsuragi is viciously beaten by Lee and crucified in the Muscle Dome. Jinno later finds Katsuragi on a big screen TV and witnesses her suffering. This motivates Jinno to intensify his efforts against Kenjin and his operations.

Jinno tracks down Kenjin’s hideout and fights through his henchmen in a hallway. Despite his efforts, Kenjin escapes by helicopter. Jinno’s confrontation with Kenjin's men shows his determination to bring justice.

Jinno is caught by police officer Ayane Katsuragi but escapes after knocking her out. His fugitive status deepens as he continues his quest to stop Blood Heat, demonstrating his defiance of authority and commitment to his mission.

While on the run, Jinno rescues young girl Haruka, whose father was forced to produce Blood Heat under threat from Kenjin. They encounter a group of orphans called the Rats, led by Ken, who refuse to aid Jinno but become part of his journey.

Jinno fights Lee Son-Min in the Muscle Dome, and the fight is broadcast with Ken planting bombs inside the arena. Ken’s sabotage causes explosions, adding chaos to the battle. Jinno finally kills Lee after a brutal fight fueled by rage.

After the fight, Ayane kills Asakura, revealing his collusion with Kenjin. Jinno follows Kenjin to an abandoned parking garage, confronting him. Lee reveals that Jinno’s anger is his greatest weapon, setting up their final showdown.

Jinno and Lee fight with sledgehammers but transition to bare-handed combat. As they fight, a mysterious figure walks out of the garage—Jinno, who has secretly killed Kenjin. Kenjin lies dead on the ground as Jinno emerges victorious.

Jinno meets with the group of orphans and the Rats, celebrating the end of Blood Heat’s circulation. His smirk indicates a sense of closure and perhaps the beginning of a new chapter after the chaos.

When asked who he is, Jinno finally smiles for the first time throughout the film, symbolizing a transformation or a moment of peace after his arduous journey. The scene caps off his character arc before the credits roll.