Clark wakes up in a laboratory on a table with his blood tainted by Kryptonite. He rushes out of the building and finds the streets of Metropolis empty. Back at the Daily Planet he runs into Lois – she has transformed into a zombie. Cut back to 12 hours earlier. Clark has an altercation with Oliver; meanwhile Tess is researching the Kandorians and gets attacked by a zombie. Clark and Lois visit Tess at the hospital only to witness her turn into a zombie. After this Clark and Lois find out that this virus sweeping across the city is brought about by sleep. It soon emerges from Emil that Clark’s blood is key to stopping the virus. Back in the present, and Clark subdues Lois just as Emil and Chloe distribute the antidote into the water supply. Clark and Oliver have a heart to heart, which end in Oliver burning his costume. The episode ends with General Zod taking a sample of Clark’s blood with the intention of tracking it.