NARRATOR: Tragic accident or calculated murder?
SVEN HAMMARBERG: Now let's see the elevations.
NARRATOR: Investigators re-open a 55-year-old mystery.
ROBERT MACINTOSH: This was a major world event.
CAPTAIN PER HALLONQUIST: We're going down. Brace! Brace!
NARRATOR: What caused a crash that killed the UN secretary general?
HENNING MELBER: It was devastating.
ROBERT MACINTOSH: This gentleman was a champion of world peace.
NARRATOR: How did a top-secret peace mission in Africa end in death?
RHODESIAN INVESTIGATOR: It's tough to see how they could screwed this up.
ROBERT MACINTOSH: Certain people believe it's just not possible that Dag Hammaerskjold was killed in a common accident. It had to be something more.
NARRATOR: Controversial theories abound.
PAUL ABRAM: Dag Hammarskjold was murdered. Period.
NARRATOR: But the truth may finally be within reach.
SVEN HAMMARSERG: As an investigator, I don't want to close any doors.