The Last Man on Earth (1964)

The Last Man on Earth features Vincent Price as a scientist who is amazingly immune (don't laugh when you find out how) to a disease which turns the rest of humanity into something other than human who crave blood. Based on Richard Matheson's book, I am Legend, Dr. Robert Morgan (Price) is forced into becoming a vampire hunter, making stakes by night and using them by day. Solitude erodes his sanity as the film progresses, making one wonder how long he will be able to continue the pursuit of his cause.