David Fincher has criticised Joker, calling it "a betrayal of the mentally ill".
The film, which won Joaquin Phoenix a Best Actor Oscar, caused controversy upon its release due to its depiction of violence and mental illness.
Upon its released in October 2019, some cinemas in the US heightened its security amid concerns of copycats.
Fincher, whose credits include Seven, Fight Club and The Social Network, has now waded into the debate during a new interview.
He accused the Todd Phillips film of "conflating" characters played by Robert De Niro in Martin Scorsese films Taxi Driver and The King of Comedy for monetary gain.
"I don’t think anyone would have looked at that material and thought, 'Yeah, let’s take Travis Bickle and Rupert Pupkin and conflate them, then trap him in a betrayal of the mentally ill, and trot it out for a billion dollars'," the director told The Telegraph.
He also attributed the film's success to Christopher Nolan's 2008 sequel The Dark Knight, in which Heath Ledger played the Joker.
"Nobody would have thought they had a shot at a giant hit with Joker had The Dark Knight not been as massive as it was," he added.
Joker was a box office success, earning more than $1bn globally.
Fincher's new film, Mank, stars Gary Oldman as Citizen Kane screenwriter Herman J Mankiewicz.
It will be released on Netflix on 4 December – read our review here.
