Patrick Dempsey is in final talks to appear in 'Bridget Jones's Baby'.

The 49-year-old actor is wanted to star alongside Renee Zellweger and Colin Firth - who's returning as Mark Darcy - in the much-discussed third installment of the franchise, Deadline reports.

Plot details of the movie remain a closely-guarded secret, although it's clear from its title that the mishap-prone Brit is unexpectedly expecting a baby.

However, it's not yet clear who fathered the child.

Earlier this year, Colin Firth revealed he was interested in the prospect of making a third 'Bridget Jones' movie.

Colin, who starred in the previous film adaptations of Helen Fielding's novels, said: ''It would have to have somewhere to go.

''Back at the time, I said that a third one should only happen if we were telling a story about having moved into a different generation when we were all beginning to deteriorate a little bit. I think we might be ready for that moment!''

However, he insisted the script would need to be right in order for him to be involved.

Colin said: ''If it feels like you're trying to squeeze something more out when it's expired then that's deathly, but they can work if they're a developing series that stays fresh.''