Griffin is a scientist who theorizes that if a person's refractive index is changed to exactly that of air and his body does not absorb or reflect light, then he will be invisible. He successfully carries out this procedure on himself, but cannot become visible again, becoming mentally unstable as a result.

London, 1907; Journalist Edward Malone, rejected by the woman he loves because he is too prosaic, decides to go in search of adventure and fame to prove himself worthy of her. Soon after, he meets Professor George Challenger, a controversial scientist who claims to have discovered a 'lost world' populated by pterodactyls and other prehistoric monsters. At an inflammatory public lecture, an expedition is organised to find Challenger's rumoured world, and Malone volunteers to go along as a r...