An island paradise home to a desolate prison and an abandoned system of caves for a secret society contain a haunting past; experts investigate the evil secrets behind these deserted places to uncover how they were built and why they were abandoned. This is a mashup of S05E08 "Curse of Satan's Catacombs," S07E03 "Secrets of Mafia Island," and S01E02 "Curse of Hell Island." 

The world's abandoned structures hold new evidence about the lives and deeds of history's greatest heroes and villains, and using the latest discoveries at these mysterious sites, experts count down the ten most significant.