Happiness

Prach investigates a mysterious murder where the victim has deep bite marks on their neck. Meanwhile, Run is taken to an operational center after surviving an attack.

Prach and Run seek the truth about the infected and the drug NEXT from Yutthasak, but the information is insufficient. Yutthasak asks them to help find the source and stop the disease, only to find the NEXT drug source linked to her new home. She and Prach pose as newlyweds to investigate.

Run and Prach moving into the condo, they meet various residents including Dr. Beam, seniors from her former school. Prach and Run observe everyone's behavior to identify the source of the drug. Simultaneously, a report of an incident at a pub sends Prach and Kai on a mission.

Meanwhile, Hack, who had turned into a madman, fought with Run and Yayee. Run and Prach learned that Hack was the one who released the drug. Yutthasak announced the lockdown of THE BREATHE condo and he was trying to find an antidote from Run's blood to save his wife.

Yutthasak ordered a condo quarantine the number of mad people increased, preventing aid delivery, causing a food shortage. Yoshi sought volunteers to get food from the minimart for compensation. Por, Jee, Prach, Run and Dr. Beam volunteered but struggled to re-enter.

Run and Prach found evidence left by Hack, they still haven't found anyone in the condo connected to Hack. Jee's clip continues to be re-uploaded, so Yutthasak ordered the disconnection of all residents' phone and internet signals in the condo to escalate control measures.

Yutthasak orders all utilities and food aid cut off to pressure the culprit out. Run is angry and worried. Prach and Run find the chief security guard's corpse, which Prach analyzes as murder. They reveal themselves as police to stop residents from arguing.

Prach finds Aem is infected. Yutthasak's past reveals his wife, she was unknowingly infected by NEXT. Prach and Run investigate the chief security guard's murder. Guard Aon, the prime suspect, flees. Run suspects another undisclosed infected person.

Tao is shot dead. Prach and Run are suspected by residents, forcing them to find the real killer.They find key evidence linking to the NEXT drug distributor. Yoshi plans to murder Sophida for her assets, but Sophida turns the tables. Yoshi sacrifices everything to survive.

Yoshi, suspected of murder, disappears from custody, released by a condo resident. Prach and Run search for him and missing resident Rangrong. Evidence of the NEXT drug case emerges, leading Prach to suspect the real killer is a resident.

Prach is bitten but saves residents. Run restores power and water. With more infected, Noi plans next steps. Yayee is scratched by security guard Aon and infected; Run must choose who gets the antibody. Yutthasak orders Arisara to rescue residents. Noi learns a secret on the 13th floor.

Sophida is killed by L1. All residents are rescued, leaving Dr. Beam. Run and Prach discover Dr. Beam is the mastermind, who created the NEXT drug and spread it for equal treatment. Dr. Beam confronts the VIP group boss involved in his parents' murder.