Moonlight spills through the shattered entrance of Asan Hospital as Jin Suk and Haejun step into the blood-stained lobby. It is already their seventh mission together. Jin Suk masks his fear with lighthearted jokes, while Haejun follows the rule they have lived by for seventeen years: if one of them is bitten, the other must end it immediately. On the fourth floor, they discover a severed zombie head lying at the center of symbols painted in blood. When the creature suddenly attacks, Haejun pushes Jin Suk aside and is bitten in his place. He tries to take his own life before the infection spreads, but Jin Suk stops him, locks him inside a medical freezer, and heads upstairs in search of a vaccine. The ninth floor has been transformed into a ritual ground ruled by a terrifying Zombie Queen with telekinetic powers. After a brutal confrontation, Jin Suk manages to recover the two remaining vaccine syringes and returns to Haejun. The moment he injects Haejun, the Queen attacks and hurls Jin Suk into a wall. Haejun awakens with superhuman strength and kills the Queen, but his eyes remain red, and he no longer recognizes Jin Suk. As he prepares to attack him, a childhood memory breaks through the infection, and he finally whispers Jin Suk's name. Dying, Jin Suk offers Haejun the final syringe the last remaining vaccine sample for humanity. But Haejun puts it in his pocket instead. Refusing to lose Jin Suk, he forces the Queen's infected blood into his mouth, choosing to infect him rather than let him die. With the unconscious Jin Suk on his back and an endless horde of zombies closing in, Haejun picks up his weapon and walks toward the fight. Beyond the hospital, the first light of dawn begins to spread across the ruined city.