Bridget Jones fans have long adored the films for their cringe-worthy, hilarious and heartwarming scenes.

But Hugh Grant has warned that the fourth instalment in the franchise – due out on Valentine’s Day next year – will have a very different tone.

Warning: If you don’t want to know about the plot of Bridget Jones 4, look away now…

“As well as being extremely funny, it’s very, very sad,” said the actor, who will reprise his role as the dashing antagonist Daniel Cleaver.

He also revealed that there was “no obvious role” for him in the film, but “they wanted to cram me in”.

Oscar-winner Renée Zellweger is also back as the title character in Bridget Jones: Mad About The Boy.

The film takes its title from the latest Bridget Jones novel, which was published in 2013.

In the book, readers rejoin Bridget in her 50s, a mother to two children and widowed following the death of her husband Mark Darcy.

Darcy was played by Colin Firth in the earlier Bridget Jones movies.

The production studio has not commented on how closely the new film will follow the storyline of its paperback namesake, but it has been revealed author Helen Fielding has written the script.

Speaking on the Graham Norton show, Grant indicated that Fielding had used a real-life tragedy to come up with the plotline.

“She had a sad story,” he said.

“She got married to an American screenwriter, she had children and then he died.”

Grant said that Fielding then started writing a novel about a woman raising children by herself, and then realised the main character was “a bit like Bridget”.

“So she made it into a Bridget Jones book,” he said.

“And as well as being extremely funny, it’s very, very sad.”

Grant, who is best known for starring in romcoms including Notting Hill and Four Weddings and a Funeral, did not appear in the third film.

He said that initially, he felt there was “absolutely no role” for his character, Daniel, in the fourth version either.

“But they wanted to cram me in,” he said.

So he said he sat down with producers to help shape the character, who was known in the earlier films for being a serial womaniser.

“I felt that what they proposed was fine, but not great.

“And I felt that he needed a third dimension, he’s in his 60s now, you can’t just have him smoothing his way down King’s Road eyeing up young girls.

“Something needs to have happened to him in the interim.

“So we invented a rather good – I invented a rather good – interim story.”

The final version got his approval, he said.

“It’s actually a very good and moving script. And I say that as someone who’s horrid about scripts. This was brilliant.”

Fielding’s first book Bridget Jones’s Diary was published in 1996 and a sequel Bridget Jones: The Edge of Reason was released three years later.

Written in the form of a personal diary, the novels chronicle the life of a hapless 30-something single working woman living in London.

In 2001, the first film adaptation starring American actress Zellweger, with Grant as Daniel Cleaver and Colin Firth as Mark Darcy, was released.

Zellweger was Oscar-nominated for the role and, in 2004, the sequel was released, although it was not as critically well received.

Emma Thompson, who debuted her character of Bridget’s despairing obstetrician in the third film, Bridget Jones’s Baby, is also set for a return in the fourth film.

New faces on the cast list include Chiwetel Ejiofor (12 Years A Slave) and Leo Woodall (One Day), who is rumoured to play Bridget’s younger love interest as she faces dating anew.

Fielding previously said she had decided to write Mark Darcy out of the series because she didn’t want Bridget to become “a smug married”, a fate deemed utterly lamentable by earlier musings of Jones.

Bridget Jones: Mad About The Boy is set for UK release on Valentine’s Day 2025.