Some of the most revered historic treasures lying in various museums around the world may be hoaxes. We examine a brass plate supposedly left by Sir Francis Drake on the west coast of North America. Looking at a fossil that changed our understanding of evolution – was it faked? Did two school boys fool the world with a decorated bone, or is it in fact a masterpiece of stone age art? Arthur C. Clarke investigates a few cases where a conclusive authenticity is almost impossible to determine.