As humans turn into savage monsters and the world plunges into terror, a handful of survivors fight for their lives — and to hold on to their humanity.
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Episode 1
Cha Hyun-su moves into the run-down Green Home by himself. Not long after, he witnesses a disturbing sight in his neighbor's apartment.
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Episode 2
As a state of emergency is declared, the residents tie up Pyeon Sang-wook for being bitten. Hyun-su is unable to ignore a family in distress.
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Episode 3
An unexpected savior protects the children from harm as Hyun-su, together with Yoon Ji-su and Jung Jae-heon, tries to bring them to safety.
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Episode 4
Critical information about the monsters is made public. When residents are split on what to do with Hyun-su, Lee Eun-hyeok suggests they hold a vote.
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Episode 5
Tasked to carry out dangerous missions, Hyun-su heads back to retrieve Han Du-sik. Sang-wook stops at nothing to finish what he started.
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Episode 6
As Seon-yeong confronts the greatest monster in her life. Leaving the building, Seo Yi-kyung heads to her fiance's office in search of answers.
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Episode 7
Hyun-su saves the others from a deadly attack. Running out of necessities, Eun-hyeok announces a plan to venture outside for resources.
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Episode 8
Having little options in her state of being, Ji-su agrees to take a big risk. Yi-kyung returns to Green Home just in time.
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Episode 9
When a team of outlaws takes over the building, the residents are shown how humans can be even more barbaric than the monsters.
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Episode 10
A military leaflet promises a route to safety, but the group is reluctant to trust it. Hyun-su is exposed to a new perspective on his condition.