I always get chills when I watch this. Actor James Woods describes being on a flight from Boston to Los Angeles. He was in first class with several other men when he noticed they were acting strangely. So strange that he called over the flight attendant and asked to speak to the captain. When the captain came out, Woods told them he was afraid the plane was about to be hijacked.
Luckily for Woods and the rest of the passengers, nothing happened that day but the FBI has confirmed that it may very well have been a dry run for the 9/11 attacks.