Collection of documentaries looking at famous conspiracy theories of the 20th century. 'JFK - Death in Dealey Plaza' looks at the unanswered questions surrounding the assassination of President John F. Kenedy in Dallas, in 1963. Was he the victim of a lone assassin, or was there a more wide-reaching conspiracy behind the killing? Includes hi-tech reconstructions and analysis of key evidence, such as the Zapruder film. 'The Death of Marilyn Monroe' looks at the unanswered questions surrounding the death of film icon Marilyn Monroe, found dead of a drug overdose in 1962. But could a single bottle of pills have been enough to kill her? Does the autopsy report indicate that she had not in fact been poisoned? Did Marilyn die at her own hand, or at the hand of another? Finally, 'Diana - Death of a Princess' looks at the unanswered questions surrounding the death of Princess Diana in Paris, in 1997. What were the factors that lead to the accident? What happened to the mysterious white Fiat spotted near the scene, and what exactly caused Diana's car to spin out of control?