Elon Musk has issued an angry tirade at the film-maker behind a four-hour documentary about his life and influence, labelling director Alex Gibney a “bitter old man” who has “zero integrity”.

Gibney, who has previously made films about the collapse of Enron, WikiLeaks and Vladimir Putin, premiered his Musk documentary at the Venice film festival this week. He said he believed the world’s richest man was “extremely dangerous”.

In a series of posts on X that Musk bought for $44bn in 2022, the tech mogul railed against the film as a “hit piece that misses”, adding its four-hour length also made the documentary, which is highly-critical of Musk, “as boring af”.

Musk also appeared to push at conspiracy theory, reposting an image depicting the Democratic party as a puppet, controlling another puppet labelled “Team Soros” – a reference to the billionaire George Soros, who has supported progressive causes.

That puppet in turn controls another labelled “Alex Gibney”, while the Gibney puppet controls another labelled “Hollywood”. In response to the picture, Musk stated: “Accurate.”

In response to a supporter who said he had never heard of Gibney until his Musk film, Musk replied: “It’s a psy op” – a reference to a planned “psychological operation” designed to influence the public’s thoughts.

“Gibney has zero integrity. Zero,” said Musk. “Fortunately, his movies are boring af … It’s a hit piece that misses, and makes the fatal sin of being boring for 4 hours.

“Gibney just assembled a hit list of people who either have an axe to grind or don’t even know me (but still have an axe to grind) … He’s a bitter old man who lost the plot long ago.

“Dogshit is worth more respect than Gibney.”

The documentary has caused stirs since its premier, as have the claims made by some of those involved in the film.

Musk specifically denied a claim made by his ex-partner, the former Maga influencer Ashley St Clair, that his team offered her $40m to sign a non-disclosure agreement about their time together.

“She was never offered that and has a history of making false claims,” he wrote.

Musk also amplified a post by podcaster Katie Miller, the wife of Donald Trump’s powerful adviser Stephen Miller and former communications director for Musk’s Department of Government Efficiency. Miller complained about the alleged absence of Musk acquaintances and allies in the film.

“It simply can’t be ‘definitive’ if the people who were present didn’t participate,” she said. “This fictional movie is a hit job by a self-obsessed Hollywood director.”

Musk’s influence on public discourse through X, and the content it prioritises, is having international ripples. While he has repeatedly intervened in the immigration debate in the UK, he also celebrated the strong result for Germany’s far-right Alternative für Deutschland in this week’s state elections in Saxony-Anhalt.

Speaking at a press conference in Venice, Gibney said he had encountered a “sense of fear” among people he approached over his film. He surmised that Musk’s childhood in South Africa may account for how he behaves now.

“He had a childhood that was very difficult and traumatic,” Gibney said. “To some extent he’s now playing out that trauma on the rest of us, if I were to psychoanalyse the situation.”