One evening in the Philippines, a wounded man was being pursued by three individuals. Seeking refuge, he approached two patrolling police officers for help. However, shortly after, another man appeared and killed both the injured man and the two officers. Meanwhile, in South Korea, Detective Ma Seok-do and his team had successfully dismantled a drug manufacturing operation. While attempting to trace the app developer used by the drug syndicate, they discovered the developer had already been murdered. The victim's mother, devastated by her son's death, took her own life. Having previously encountered her, Ma Seok-do was deeply affected and vowed to bring the perpetrator to justice. The killer was identified as Baek Chang-gi, a former mercenary known for his ruthless nature. Operating illegal gambling establishments in the Philippines under orders from his boss, Jang Dong-cheol, Baek grew increasingly resentful due to Jang's repeated betrayals, including an attempt to have him eliminated. Determined to confront Jang, Baek traveled to South Korea to settle the score.