Daybreakers

It's 2019. A decade ago a bat-borne plague swept the world and converted most of humanity into vampires, who promptly rebuilt civilization in their image — underground walkways, UV-proofed cars, permanent night shifts, and a blood corporation called Bromley Marks that keeps the remaining humans in suspended tanks and drains them to supply the population. The farms are running dry. The blood shortage is becoming a crisis.

Edward Dalton is a hematologist at Bromley Marks tasked with developing a synthetic substitute. He's a vampire who refuses to drink human blood and privately opposes the farming system, which puts him at odds with his boss Charles Bromley — a cold, pragmatic man whose own daughter chose death over vampirism. Edward's brother Frankie is a soldier who hunts escaped humans.

The shortage is producing a second crisis: vampires deprived long enough don't simply starve — they mutate. They devolve into feral, bat-like subsiders that haunt the underground tunnels. The government hunts and destroys them, but the numbers are growing faster than they can be contained.

Edward nearly runs down a group of humans fleeing soldiers and helps them escape. Among them are Audrey and a man called Elvis — a mechanic and former vampire who was accidentally exposed to sunlight and running water during a car accident and found himself cured. He's been human ever since. Elvis believes the combination can be replicated. Edward agrees to help them find a reliable process.

The synthetic blood project fails. The shortage tips into catastrophe — vampires are starving in the streets, subsiders multiply, the social order fractures. Bromley discovers Edward's involvement with the humans and moves to capture him. Edward escapes with Audrey and Elvis.

They refine the cure: controlled sunlight exposure followed by water immersion. Edward submits to it and becomes human. The question becomes delivery — how do you distribute a cure in a world that built itself around never needing one? The answer arrives violently: when a cured vampire is fed upon by another vampire, the cure transmits through the blood. Those vampires revert to human. Other vampires feed on them. The chain reaction is brutal and unstoppable.