Part 5/9:
Encouraged by his findings, Jung collaborates with the KCDC, conducting experiments that reveal the humidifiers were contaminated with a toxic disinfectant known as PHMG. This biocidal agent has dangerous properties, causing acute lung failure. The substance was contained in a humidifier disinfectant marketed as "Spotless," previously approved by health authorities obsessed with profit rather than public safety.
As Jung continues his quest for justice, he enlists the help of his sister-in-law, Han Youngju, an attorney who faces significant challenges in taking on the powerful corporation behind "Spotless." Despite facing obstacles, Youngju's determination drives her to expose the deceptive practices of the O2 company, pushing for media coverage that would ignite a public outcry.