I Am Legend by Richard Matheson (The original book) - Is well worth taking the time to track down and read. Well written, clever, and Robert Neville is a good character. He's not a scientist (as he has been portrayed in each of the cinema versions) and decides to try and learn about the illness that is turning people into vampires. He's fallable, makes mistakes due to impatience, and is generally fairly believable. ( The three film versions reviewed and pretty much spoiler free for all bar the most pedantic spoiler avoider... )
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