60 years on from the assassination of US President John F Kennedy, and there are still so many questions about that shocking day in November 1963. Why did Lee Harvey Oswald want to kill JFK? Did he act alone? A new theory has emerged from a filmmaker who never set out to answer any of those questions, Mary Haverstick. But while making a film about a group of female aviators training to be astronauts in the late 50's, she came across the story of Jerrie Cobb. With classified documents accidentally landing in her lap, Haverstick tells the story of a woman who may have been a spy and part of the team that attempted to assassinate Fidel Castro and possibly an accomplice to Lee Harvey Oswald. Her book is called A WOMAN I KNOW: Female Spies, Double Identities, and a New Story of the Kennedy Assassination.