Little is known about what character Stacy Keach is playing, although it is believed he will perform alongside Joan Allen and Albert Finney, who are a part of the covert Treadstone program. Joan Allen appeared in The Bourne Supremacy and The Bourne Ultimatum, while Albert Finney made an appearance in The Bourne Ultimatum. Both actors will reprise their same roles in The Bourne Legacy
Jeremy Renner is attached to star as an unknown assassin who is trained in the Treadstone program. Matt Damon will not return as Jason Bourne from the original trilogy, although The Bourne Legacy is set in the same environment.
Tony Gilroy, who wrote The Bourne Identity, The Bourne Supremacy, and The Bourne Ultimatum, is writing and directing The Bourne Legacy. No production schedule has been given for The Bourne Legacy yet, although an August 3, 2012 release date has already been set by Universal.