The Bourne films are a series of action spy thriller film based on the character Jason Bourne Matt Damon, a CIA assassin suffering from extreme memory loss who must figure out who he is, created by author Robert Ludlum. The Bourne Legacy introduces a new main character, Aaron Cross Jeremy Renner, a Department of Defense operative who runs for his life because of Bournes actions in Ultimatum.
A man Matt Damon is found floating in the Mediterranean Sea with two gunshot wounds at his back and a device with the number of a Swiss safe deposit box embedded in his hip. Upon reaching shore, the man assumes the name Jason Bourne after finding a passport under the name in the safe deposit box, along with other international passports, large amounts of assorted currencies, and a gun. He subsequently attempts to discover his true identity while countering attempts on his life by CIA assassins, eventually realizing that he is one such assassin who failed to complete his most recent mission. Bourne breaks his connections to the CIA and unites with Marie Kreutz Franka Potente, a woman who helped him learn about his most recent actions prior to his memory loss. Bournes conflict with the CIA reaches a climax when he takes the fight to their doorstep.Some two years after learning that he is a trained assassin and breaking his connections with the CIA, Jason Bourne Matt Damon is framed for a crime connected to one of his past missions. A subsequent attempt on his life results in Maries death, so he decides to take revenge by hunting down those responsible for her death and his forgotten past, thinking that the CIA is hunting him again. Bourne discovers that Ward Abbott Brian Cox, one of the men who oversaw Operation Treadstone, the program which trained Bourne to be an assassin, stole millions of dollars from the CIA. Abbott meant to implicate Bourne in the theft with the frameup, which would have led the CIA on a wild goose chase had Bourne been killed as intended. Bourne exposes Abbott to Pamela Landy Joan Allen, the CIA officer in charge of finding Bourne, and Abbott commits suicide. During a long car chase with Bourne, the Russian agent who was paid to kill him and was responsible for Maries death is killed, and Bourne goes into hiding. Bourne also figures out what his real identity is. ........
Source: Wikipedia