The Age of Shadows

Kim Jang-ok and Joo Dong-sung visit Kim Hwang-sub, pretending to seek military funds for their cause. However, they are ambushed by Japanese forces, leading to a perilous and fateful encounter.

In the midst of the ambush, Kim Jang-ok engages in a fierce gun battle against overwhelming Japanese forces. Despite his bravery and fighting spirit, he ultimately faces his tragic fate when confronted by his former friend, Lee Jung-chool.

Following the ambush, internal suspicion arises amongst the Heroic Corps members. Jo Hwe-ryung accuses Joo Dong-sung of being a traitor, prompting Kim Woo-jin to intervene decisively by banishing Joo from their ranks.

Japanese authorities assign Lee Jung-chool to keep an eye on Kim Woo-jin after the recent events. Despite their past connection, both men discreetly recognize that they must maintain a facade of friendship amidst the brewing tension.

Lee is paired with Hashimoto, who is tasked with monitoring Lee himself rather than aiding him. As surveillance tightens, Lee takes measures to protect the Heroic Corps while buying them time for their next move.

The Heroic Corps narrowly escapes to Shanghai as the pressure mounts on their operations. There, they regroup under leader Jung Chae-san, who persuades Lee to join their cause amid the swirling tide of danger.

Under immense pressure to act, Lee decides to assist the Heroic Corps in smuggling explosives back to Korea. His decision marks a pivotal shift in loyalties as he grapples with his previous allegiances and the ongoing struggle for freedom.

Back in Korea, Lee alerts Kim Woo-jin about the presence of a mole within their ranks. To uncover the traitor, Kim sets a trap by feeding different rendezvous times to each member, setting off a chain reaction of revelation.

The spy within the Heroic Corps is revealed to be Jo Hwe-ryung, leading to a dramatic confrontation. In an act of ruthless justice, Kim executes him aboard a train, reinforcing the group's commitment to their cause.

As the Heroic Corps arrives in Gyeongseong, they are confronted by Japanese police, resulting in a violent shootout. In the ensuing chaos, many members either perish in battle or are captured, leading to a significant loss for the resistance.

Lee, now under suspicion from the Japanese authorities, is ordered to find Kim. To maintain his cover, he resorts to torturing Gye-soon, showcasing the painful lengths he must go to protect the Heroic Corps.

In a shocking turn of events, Lee is tricked by Joo Dong-sung and inadvertently leads the authorities to Kim's hideout. After a desperate escape attempt, Kim is captured, revealing the fragility of their struggle.

To protect vital information while being tortured, Kim bites off his own tongue, illustrating his unwavering commitment to the cause. Meanwhile, Lee feigns loyalty to the Japanese in hopes of securing a lighter sentence.

Upon his release, Lee learns about Gye-soon's tragic death and feels compelled to act. Remembering Kim's final wish for someone to survive and complete their mission, he devises a plan to plant explosives at a gathering of collaborators.

The bomb detonates at the party, resulting in the deaths of high-ranking officials including Higashi. In prison, a mute Kim Woo-jin learns of the successful operation and finally smiles, knowing his sacrifice bore fruit.

In the aftermath, Lee tracks down Kim Hwang-sub, the man whose betrayal led to Kim Jang-ok's death. In a powerful act of vengeance, Lee kills him, avenging his friend and solidifying his transformation.