Since the German authorities are determined that they have found the man responsible for Madeleine McCann's disappearance back in 2007, ITV released a documentary based on the unsolved case - and it is by far not the first documentary dedicated to telling the story of a person who vanished without a trace, and appealing for information. Here are five documentaries dedicated to discovering the truth about what really happened to long lost missing people...
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The Disappearance of Madeleine McCann
This 2019 Netflix documentary took a detail look into what happened to Madeleine McCann, a three-year-old girl who vanished from her hotel room in Praia de Luz in Portugal. The series looks at how to Portuguese police worked with Scotland Yard to launch one of the biggest investigations - and certainly one of the most high-profile missing children's cases - in history.
Madeleine McCann: The Hunt for the Prime Suspect
The new ITV documentary looks at the latest news in Madeleine's disappearance case; and how the German authorities have a prime suspect, Christian Bruckner, and explores claims that the police made several mistakes which stopped him from being named as a suspect earlier.
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It also looks at how these sorts of cases have been handled since Maddie's disappearance, with criminologist Dr Hill suggesting that nothing would change. He said: "You can abduct a child in one European country. And in 24 hours drive right across Europe. And I'm not so sure that much or anything different will be done because I'm not so sure we've learned the lessons."
Unsolved Mysteries is an anthology documentary which looks at a different, almost impossible unsolved mystery in each episode. While some episodes look at mysterious deaths or UFO sightings, it also looks at different people who appear to have vanished without a trace. Speaking to the family and friends of the missing persons, it is a heartbreaking look into the impact unsolved cases have on the lives of those involved.
Cold Case Files
This documentary, hosted by Bull Kurtis, looks at the investigations into long-unsolved disappearances and murders in the hope of finally finding a breakthrough in the case, sometimes decades later.
The Investigator: A British Crime Story
The synopsis for this ITV show, which is now available on Netflix, reads: "This eerie true-crime series reopens the mysterious case of Carole Packman, who utterly vanished in 1985, and the husband convicted of her murder." Carole was a housewife who disappeared days after visiting a solicitor to begin divorce proceedings.
Abducted in Plain Sight
This stranger-than-fiction one-off documentary film follows the 1974 case about Jan Broberg, a 12-year-old girl at the time, who was groomed and eventually kidnapped by a family friend, who had slowly brainwashed her family into blindly trusting him with their daughter, even dropping charges against him and allowing him back into their lives after Jan had been returned home safely.