From Patrick Kennedy's emigration in 1849 to the death of JFK Jr. in 1999, the films charts the family's rise from poor Irish immigrants to an all-powerful dynasty, exploring the lives, careers, personal tragedies and scandals that have given rise to the idea of a Kennedy curse.
Featuring interviews with family members, and including rare archive, photos and letters, 'The Kennedys: A Fatal Ambition' sets the events in historical context, examines the family's unique characteristics and asks what part they may have played in many of the misfortunes.

Tony Accardo receives a phone call from Joseph P. Kennedy, asking the mob kingpins to use their pull with the Illinois union vote to help his son, John F. Kennedy, win the upcoming presidential election. In return, he offers to put an end to his son Robert F. Kennedy's investigation into Giancana and the Outfit. As election day nears, Kennedy's fight against Richard Nixon tightens, turning Illinois into a key battleground. Giancana delivers the union votes. After a close race, Kennedy is declared the victor. Just weeks after Kennedy takes office, his brother Robert is named Attorney General. To the Chicago mob's surprise, when Robert takes office as the new U.S. Attorney General in 1961, he makes his top priority going after organized crime ó and one of his primary targets is the Outfit. Weeks after, John F. Kennedy is shot and killed in Dallas. After his brother is assassinated, Robert steps down from his post as Attorney General and the investigation into organized crime is virtually dropped. The government begins an investigation into the assassination, with rumors already circulating that the mafia could have been involved.