In a post-apocalyptic world torn apart by biological warfare, a virus has transformed the majority of humanity into nocturnal, albino mutants known simply as "The Family". These mutants shun all forms of technology and believe that the disease was a punishment for mankind's sins, actively hunting the remaining humans and destroying remnants of the old world. Amidst the desolation roams Robert Neville, a former military scientist, who appears to be the last uninfected human in Los Angeles. By day, he scavenges for supplies and searches for a cure to the virus that he is immune to, thanks to a vaccine he developed. His days are marked by solitude and the constant threat of attack from The Family, who seek to kill him for being a symbol of the world they despise.

Neville fortifies his home against the mutants and battles them with the aid of technology and weapons, maintaining a semblance of normal life despite the chaos. His loneliness and the burden of potentially being the last human alive weigh heavily on him. A glimmer of hope emerges when Neville encounters other survivors. Together, they face the daunting task of outsmarting The Family, striving to rebuild some form of society amidst the ruins. The story weaves the themes of survival, the effects of isolation on the human psyche, and the clash between the remnants of the old world and the new order established by The Family.