The narrative architect behind the Bourne film series, Tony Gilroy, takes the helm in the next chapter of the hugely popular espionage franchise that has earned almost $1 billion at the global box office: The Bourne Legacy. The writer/director expands the Bourne universe created by Robert Ludlum with an original story that introduces us to a new hero (Jeremy Renner) whose life-or-death stakes have been triggered by the events of the first three films.

For The Bourne Legacy, Renner joins fellow series newcomers Rachel Weisz, Edward Norton, Stacy Keach and Oscar Isaac, while franchise veterans Albert Finney, Joan Allen, David Strathairn and Scott Glenn reprise their roles.

"Jason Bourne was just the tip of the iceberg."

For the last decade, the Bourne franchise has been arguably the definitive series to beat when it comes to delivering the mechanics, both structural and cinematic, of modern spy films.

Since The Bourne Identity (2002) hit theaters with a resounding box-office bang with star Matt Damon and director Doug Liman, who passed on the directorial baton to Paul Greengrass for The Bourne Supremacy (2004) and The Bourne Ultimatum (2007), the franchise has given new impetus and styling to films about espionage, national security, and trained assassins, while at the same time retaining the mainstream entertainment value of the genre, best represented over the last half-century by the ubiquitous James Bond films.

The title of the franchise's latest incarnation hints of a deeper emphasis on the impact of Jason Bourne's persistent existence on the national security policies and execution of the controversial medical-intelligence programme designed to alter the physical and neural-behavioural manners of its 'programme participants'.

The Bourne Legacy does its best to give audiences a third-party view of the panic Jason Bourne has created, by following two narrative threads, one running parallel to the events that happened in The Bourne Ultimatum, and the other focusing on Aaron Cross (Jeremy Renner), a 'programme participant' primed for assassination by covert agents in a bid to remove evidence and close down operations.

Written and directed by Tony Gilroy, who co-wrote the screenplays for the previous three installments, The Bourne Legacy is an assured action spy thriller. It is well-directed with good performances by Renner and especially Rachel Weisz, who plays a scientist who suffers a traumatic experience, and inevitably becomes Cross' love interest and more.

While there is less intense drama and lingering suspense as compared to its predecessors, The Bourne Legacy makes up for them with some excellent action sequences, most notably the third act, which is an entire, lengthy action set-piece by itself.

The Bourne Legacy echoes the style and spirit of the Bourne franchise, albeit inconsistently. It may also be accused of being derivative of Ultimatum's blend of rooftop foot chases and motorbike chases, as if Gilroy is trying to outdo Greengrass' stupendous display of technique and skill in crafting intricate and intense action.

Still, I enjoyed the film for what it's worth, though I must warn that The Bourne Legacy will not make sense to newcomers without some knowledge of the screen versions of the Bourne franchise. There are also some unnecessary medical and scientific jargon added that will bore viewers.

In my opinion, Gilroy has done his best film yet after the severely overrated Michael Clayton (2007) and the delightfully-flawed Duplicity (2009). For a Hollywood blockbuster, this is decent offering, a mile better than movies like Salt (2010). If it is anything to note, Gilroy is an improving filmmaker, and I'm interested in a fifth 'Bourne' picture if Gilroy puts his name on it.

Verdict: An assured action spy thriller that echoes the spirit of the Bourne franchise, but remains derivative.