Always fascinated me has the Roswell incident. Presumably thats because I know so little about it. Today its peaked my interest for no reason other than fascination with conspiracy theory, alien visitation and the like. So here's my attempt to break it into understandable chunks (I assume before reading further that the story has been written, re-written, changed, added to, etc over the past 50 years)

Key Personnel:
William "Mack" Brazel - Discovered debris on his ranch from a crashed aircraft.
Colonel William Blanchard - Commander of the Roswell air force base to which Brazel took the debris
Major Jesse Marcel - Head of intelligence at Roswell Air Force Base
Sheridan Cavitt - Roswell Army Counterintelligence Officer
Brigadier General Roger Ramey - Head of the Eighth Air Force
Brigadier General Thomas Dubose - Chief of staff for Ramey - claimed to have been ordered to begin coverup by Washington

Key Dates and times
Early July 1947: Brazel discovers pieces of debris on his ranch and takes them to the Air Force base in Roswell. Here, Blanchard immediately makes a statement that they have part of a downed alien spacecraft. Almost immediately after this, a higher ranking Air Force officer (Ramey) orders a cover up and the cover story is to be a weather ballon.