In what was previously known as the Bourne Trilogy — “Identity,” “Supremacy” and “Ultimatum” — Damon set the bar high as the former CIA black ops assassin stricken with traumatic amnesia and going on the lam to learn his true identity as his former Langley handlers strove to track him down and eliminate him with extreme prejudice. The three-film arc formed a coherent dramatic journey, culminating in director Paul Greengrass' sleek, stripped-down and satisfying third installment.
To pick up the thread of “The Bourne Legacy,” and the similar plight of Renner's CIA killing machine Aaron Cross, it's necessary to remember the events of “Ultimatum,” where Bourne finally pieced together his place in the uber-secret Treadstone and Blackbriar operations and his role in their deadly, illegal missions.
Events in “Legacy” partly overlap with the climax of “Ultimatum,” in the aftermath of Bourne's dogged determination to air the truth and CIA brass scramble to clean up the embarrassing mess. That includes scrapping Treadstone and Blackbriar and abruptly shutting down a third, even more radical off-the-books program, Operation Outcome. The dark secret of Outcome is that its agents underwent genetic enhancement to make them exceedingly deadly and resourceful.
Tasked with sweeping it all under the carpet is ruthless CIA operations manager Eric Byer (cool, calculated Edward Norton), who begins by overseeing the elimination of all Outcome agents and scientists. That's when we first meet Cross, who narrowly escapes death in a drone missile attack on a remote Alaskan outpost.