A 1950s memo on space aliens and a UFO crash is the most searched for document in the FBI's "vault."
CNN's Brian Todd explains why it's stirred so much intrigue among users of the FBI's digital reading room.
MORE VIDEO: Public captivated by flying saucer report
Morning Express with Robin Meade airs Monday through Friday at 6 a.m. ET on HLN. Like the show on Facebook, follow on Twitter: @MorningExp.