Happiness (South Korean TV series)

Setting

Happiness takes place in the near future, where the release of a failed treatment drug "Next" has caused a worldwide pandemic known as the Lytta Virus, a.k.a. "mad person disease". Those infected by Lytta experience short bouts of insanity and bloodlust, before completely regressing into a zombie-like state. The South Korean Military and Police forces try to contain the spread of Lytta and Next through extensive investigation and authoritative quarantine measures, while civil rights groups protest against them, believing the infected are still capable of normal human interaction.

Plot

Yoon Sae-bom encounters a trainee at the Special Operations Unit who is infected by mad person disease. In the struggle to subdue the trainee, she is scratched, leading her to meet Han Tae-seok at a research facility. The facility houses many of the "patients" who are kept under observation in order to understand and cure the disease. It is revealed that the symptoms of mad person disease are first accompanied by unabated thirst, followed by the pupils turning white, and then thirst for human blood. The disease is not airborne, but spreads through scratches and bites, with Yoon Sae-bom seemingly immune to the disease. Some of those who contracted the disease are ultimately able to return to their former selves temporarily. Yoon Sae-bom makes a deal with Han Tae-seok which leads her to secure an apartment in a newly constructed building. However, in order to do so, she must be married, so she asks her high school friend Jung Yi-hyun, a former star baseball player but now a police detective, and he agrees to a contract marriage. The building is luxurious and stratified, with public rentals making up the first five floors, and those who own apartments for the upper ones. Class discrimination is evident when upper floor resident Oh Yeon-ok struggles at being the apartment's representative while keeping everyone in check. Yoon Sae-bom meets interesting and strange residents, forming a close attachment to her neighbor's young daughter.

Through Jung Yi-hyun's detective work, he encounters a diseased person who he believes became this way due to a failed pneumonia drug called Next, which had been widely circulated in order to promote attentiveness and strength. This assumption is later confirmed when a resident member who consumed the drug, secretly sold to her in the building's gym, ultimately becomes infected with the mad person disease and succumbs to the illness. This begins the outbreak in the building. In an effort to protect the residents in his building, Jung Yi-hyun and Yoon Sae-bom establish quarantine rules, while securing the building from the outside with the help of his captain, Kim Jung-guk. Jung Yi-hyun conflicts with building resident Oh Joo-hyung, who seems to encourage destructive behavior in the building. The question of humanity and whether to view those infected with mad person disease as human beings forms a psychological battle for Sae-bom, Yi-hyun and Tae-seok.

Han Tae-seok initially tries to keep the mad person disease a secret, but with more cases progressing and people getting panicked, the secret is revealed to the public. With an increasing number of people getting infected, Han Tae-seok and his military team struggle to determine whether to preserve these people or kill them off. Han Tae-seok orders the complete quarantine of the new building complex where Yoon Sae-bom and Jung Yi-hyun live, offering them a chance to leave the building before it becomes completely sealed off. However, they decline the offer. Yoon Sae-bom's blood contains antibodies that could hold the cure for the disease, which Han Tae-seok seeks to exploit. It is revealed that Han Tae-seok's pregnant wife was bitten by the president of the pharmaceutical company that supplied Next, and ultimately became infected with the disease. His search for the cure is in part motivated to find a cure for his wife and to save his unborn child.

Main

• Han Hyo-joo as Yoon Sae-bom

A member of a Special Operation Unit police squad (KP-SOU) formerly known as KP-SWAT. She was excited to move into her new apartment, but as soon as she moves there she faces a crisis.

• Park Hyung-sik as Jung Yi-hyun

A detective who has romantic feelings for Sae-bom; they graduated from the same high school. He struggles to protect Sae-bom and other people.

• Jo Woo-jin as Han Tae-seok

A lieutenant colonel and part of the health service command. He holds a key to the infectious disease outbreak.

Supporting

People around Jung Yi-hyun

• Seo Hyun-chul as Yi-hyun's father^[9]
• Jung Jae-eun as Yi-hyun's mother^[9]
• Lee Jun-hyeok as Kim Jung-guk^[9]

Yi-hyun's supervisor.

Extended

• Baek Hyun-jin as Oh Joo-hyung^[10]

A dermatologist.

• Han Da-sol as Bo-ram^[11]

A mart employee.

• Lee Ji-ha as Jo Ji-hee^[12]
• Moon Ye-won as Woo Sang-hee^[13]

A dermatologist.

• Park Hee-von as Na Hyun-kyung^[14]

A romance web novelist.

• Park Hyung-soo as Kook Hae-seong^[15]

A lawyer.

• Park Joo-hee as Ji-soo^[16]

A lieutenant.

• Kim Young-woong as Go Se-kyu^[17]
• Na-cheol as Na Soo-min^[18]

Na Hyun-kyung's brother.

• Cha Soon-bae as Seon Woo-chang^[19]

A pastor.

• Yoo Ji-yeon as Colonel Han Tae Seok's wife^[20]
• Lee Joo-seung as Andrew^[21]

A cleaning company employee.

• Han Joon-woo as Kim Se-hoon^[22]

An intellectual who moves around the world with his diplomat parents.

• Kang Han-sam as BJ Kim Dong-hyun^[23]
• Bae Hae-sun as Oh Yeon-ok^[24]
• Hong Soon-chang as Kim Hak-je^[25]
• Lee Joo-sil as Ji Sung-sil^[25]
• Kim Ju-yeon as Kang Eun-ji^[25]

Seo-yoon's mother.

• Nam Mi-jung as Lee Deok-soon^[26]

A cleaning lady.

• Jung Woon-sun as Shin So-yoon^[25]
• Joo Jong-hyuk as Kim Seung-beom^[25]
• Song Ji-woo as Park Seo-yoon^[25]

Special appearances

• Lee Kyu-hyung as Lee Seung-young (eps. 1–3, 8, 12)^[27]
• Baek Joo-hee as Park Min-ji (eps. 2–3)
• Lee Seung-joon as Kim Dae-yoon (ep. 12)

A brigadier general.

Part 1

Part 2

Part 3