Film critics have offered a range of views about Joker: Folie à Deux, starring Joaquin Phoenix and Lady Gaga, calling it both "bleak and daring", but also "depressingly dull and plodding".

Folie à Deux, directed and co-written by Todd Phillips, premiered at Venice Film Festival, and Geoffrey Macnab described it in the Independent as "just as bleak and daring as the original".

But David Ehrlich wrote in IndieWire that "Phillips’ musical sequel feels like it’s bad on purpose", adding that it was "boring, flat, and such a criminal waste of Lady Gaga that we should demand a public hearing."

Critics were similarly divided over the first Joker film, which came out in 2019 and earned Phoenix an Oscar.

It also won the top Golden Lion prize at Venice and was the first R-rated film to make $1bn at global box office.

Lady Gaga plays Harley Quinn, Joker's love interest, and she also sings in the film, along with Phoenix, who returns as the troubled Arthur Fleck who transformed into murderous clown Joker.

Speaking at the premiere, which she attended with her fiancé Michael Polansky, she said she decided to co-star in the film to "help people feel good about life" and allow them to "escape into another world".

She also told Vogue, in its upcoming October edition: “Harley Quinn is a character people know from the ether of pop culture. I had a different experience creating her, namely my experience with mania and chaos inside - for me, it creates a quietness.

"Sometimes women are labelled as these overly emotional creatures and when we are overwhelmed we are erratic or unhinged.

"But I wonder if when things become so broken from reality, when we get pushed too far in life, what if it makes you…quiet?”

Joker meets Harley Quinn while they are incarcerated at Arkham State Hospital, and they later pursue a dark romantic adventure together, which includes some musical numbers.

But in his review, Ehrlich added: "Phillips seems physically incapable of - or actively uninterested in - shooting a musical setpiece with any visual panache to it whatsoever...

"It certainly isn’t interesting to watch, as most of the tunes are pared down into dull cabaret arrangements and shot against the black void of the characters’ shared imagination."

However, Macnab gave the film four stars, saying it stars "a stirring, emaciated Joaquin Phoenix and an appealingly cruel and feline Lady Gaga".

He said Phillips is "clearly having fun" with the film, which opens with "some inspired, Looney Tunes-style animation... then becomes a Shawshank-esque prison movie, then a musical, then a courtroom drama."

He added that while the "lines between fantasy and reality aren’t always made clear", the movie is "just as edgy and disturbing as its forerunner, replicating the idea of modern American cities as terrifying powder kegs perpetually on the cusp of explosion".

But Hollywood Reporter's David Rooney called the film "frustrating", saying it was "most electric when Joaquin Phoenix and Lady Gaga sing, dance and romance".

In Screen Daily, Tim Grierson added that the two leads "fail to spark", and the movie is "without the insight that made the original film so engrossing and unsettling". But he noted that it still "seems poised for strong box office".

The Guardian's Peter Bradshaw said the film "spirals out of tune" and called it "claustrophobic and repetitive".

But he preferred it to the first film, saying: "Though it ends up as strident, laborious and often flat-out tedious as the first film, there’s an improvement.

"It’s a musical, of sorts, with Phoenix and others warbling show tune standards, often in fantasy set pieces, a little in the way of Dennis Potter’s Pennies from Heaven. This gives it structure and flavour that the first film didn’t have."

In Deadline, Pete Hammond said the film was an "audacious and head-spinning follow-up" to Joker, and he praised "production values across the board" as "excellent", including the return of composer Hildur Gudnadottir, who won an Oscar for the first film's score.

"With song, dance, comedy, darkness, animation, drama, violence and more, this is a musical - if it even is a musical - like no other," he added.

But while The Wrap's William Bibbiani called the film "impressively odd", The Evening Standard's Jo-Ann Titmarsh said it was "depressingly dull and plodding".

Phoenix lost weight for the first film, and was asked about it again when he reprised the role.

Ehrlic commented in IndieWire that "Phoenix looks even skinnier here than he did in Joker, his shoulder blades threatening to cut two holes straight through his back".

Variety said the actor admitted at the press conference that his weight loss was a ‘"bit more difficult" for the sequel because of the dance component, saying it was "safe" but "I probably shouldn’t do this again".

"This time, it felt a bit more complicated just because there was so much dance rehearsal that we were doing," he said.

Director Todd Phillips previously told USA Today he wanted the Joker to look "malnourished and thin and hungry."

Variety's critic Owen Gleiberman added the film was a "cracked jukebox musical - but it doesn’t let Joker be Joker enough".

"The concept is audacious but the execution less so in a movie that takes a step back from the danger of Joker," he added.

The film is released in UK cinemas on 4 October.