On April 20th, 1925, British explorer Colonel Percy Fawcett, together with his son, Jack and friend, Raleigh Rimmel, set off from the frontier town of Cuyaba, Brazil into the Amazon jungle. They were in search of a large, ancient city that Fawcett was convinced had lain hidden for hundreds of years.

It was 57-year old Fawcett's second attempt to find the lost city. He had tried once before, in 1920, but gave up in frustration after three months. Fawcett wrote his wife a letter from Dead Horse Camp on May 29th, ending: "you need have no fear of failure…." It was the last time anyone heard from him. Fawcett and his two young companions were never to be seen again.

Were they murdered by native tribesmen? Did they fall victim to a virulent jungle virus? Or did they find the lost city, and spend the rest of their days there in splendid isolation?