Three different endings were filmed for this movie. None of the cast members knew which one was used until it opened in cinemas.
According to Colin Firth, his new rival, Patrick Dempsey's Jack Qwant, is more intimidating than his former opponent, Hugh Grant's Daniel Cleaver. "Mark didn't think Daniel was better than him. This guy Jack seems to be more of the charming good guy, and in some ways that's scarier."
This is not a movie adaptation of Helen Fielding's "Bridget Jones: Mad About the Boy", the third novel in the Bridget Jones series, released in 2013. Instead it's based on an original screenplay which Fielding wrote with David Nicholls.
Hugh Grant was initially set to rejoin the cast for this movie as Daniel Cleaver, but eventually he declined, due to not liking the script and not seeing how the character could fill into the story without changing him dramatically, something he didn't want.