On February 22, 2008, Variety reported that a fourth film was indeed in the works,
with both Damon and Greengrass on board.[28].
The scene featuring Bourne desperately trying to catch a glimpse of Paz in the London
Underground after Ross is gunned down is, according to Greengrass, an homage to the New York City Subway
chase in one of his favorite films, The French Connection.