Can you give an example of a documentary where the person telling the story believed it to be true, but it turned out to be false?

Read also:

• The Labour Party wants to put the Winter fuel allowance and the £800,000 of gifts received by ministers behind us. Is this a real option for the people who will suffer as our new masters unapologeticly feast on freebies?
• What is the reason behind the Russian government's negative view on foreign travel?
• My cantankerous beagle is very badly behaved at the dog park and always starts barking at the other dogs. Would pepper spray be an effective method to correct his inappropriate behavior?
• How do we greet in German, French, Spanish, and Italian?
• How could NASA possibly land on the moon when it's impossible to reach the moon through the Earth's dome? Why are they making up such an obvious lie?
• What do you think hell is like?
• Why do we exist, and why are we conscious?
• What are some sad truths about life?
• Can you name a female actress who has had bad timing or luck in her film career?
• Have you ever seen a woman having sex with a dog?