In the rarefied world of international espionage, where discretion is considered the better part of valor, no one expects you to be the life and soul of the party.

But shadowy former CIA operative Jason Bourne is laconic even by a spy's standards, according to US actor Matt Damon, who has revealed his iconic character has just 25 lines in the latest Bourne film.

The amnesiac superspy returns to the big screen next week for the first new installment of the Robert Ludlum-based thriller series since 2012, and the first starring Damon in nine years.