A young Australian actor at the centre of a multimillion-dollar defamation case in the US alleges in documents filed to the Los Angeles superior court that Rebel Wilson made up lies about her and bullied and harassed her on the set of The Deb.

Charlotte MacInnes, who stars in the comedy which premiered at the Toronto international film festival in September, alleged in the documents that Wilson repeated claims that one of the film’s three producers, Amanda Ghost, sexually harassed and abused MacInnes, even after she told Wilson no such behaviour had occurred.

“I was deeply disturbed by this behaviour, and felt very bullied and harassed by Wilson, who was the director of the film and in a position of authority over me,” MacInnes alleged.

“Nothing that I told Wilson could reasonably have conveyed that I was reporting any misconduct, because there was no misconduct.

“I also understand [there were] claims that I was subjected to ‘depraved sexual demands’ and that ‘MacInnes remains captive by Ghost and Cameron as she is shuttled from city to city with them including Boston, New York, and London’.

“These statements are completely false and absurd. I have no idea what could cause Wilson and her attorney to make up such lies about me.”

The alleged sexual misconduct is one of three key accusations by Wilson that the film’s three producers, Ghost, her husband Gregor Cameron, and Vince Holden are suing the Australian for defamation over.

On Wilson’s Instagram account which has more than 11 million followers and in her declarations filed to the court, Wilson has also accused Ghost and Cameron of scheming to embezzle A$900,000 of The Deb’s funding, along with various bullying and unlawful imprisonment allegations.

Wilson is countersuing and seeking to use California’s anti-Slapp laws, designed to protect freedom of speech on matters of public interest, to strike the defamation claims made against her.

Lawyers acting for the producers filed a motion to strike Wilson’s claim late on Friday LA time, alleging Wilson’s declaration in support of her motion included “multiple blatant falsehoods and rises to the level of outright perjury” and that Wilson’s complaint focused on a private business dispute, not a public issue.

Documents lodged include MacInnes’s declaration, along with statements that offer further evidence on the wrangling over The Deb’s writing credits, which appears to have further inflamed the dispute that could now see both sides’ legal bills run into the millions.

Lawyers acting for the producers have requested a 90-day stay in proceedings to establish the source of an anonymous website they say accused Ghost, a British-born producer of Indo-Trinidadian heritage, of being an “Indian Ghislaine Maxwell”.

The argument for the stay includes allegations the website, which contained “grotesque lies”, was registered with the domain name amandaghost.com two days after Wilson sent threatening emails warning she was poised for “going public” to “very publicly ruin them”.

Lawyers acting for the producers also allege Wilson’s lawyer, Bryan Freedman, sent the producers an email threatening to “blow up” one or more of the plaintiffs in a public filing that included “sex trafficking”, which he said “can’t be good for the film”.

The producers have also filed statements alleging Wilson threatened the film’s writer Hannah Reilly, the recipient of the Rebel Wilson theatremaker scholarship that is administered through the Australian Theatre for Young People, which resulted in her play being turned into a film.

After Reilly refused to grant Wilson writing credits for the film, Wilson turned to the Australian Writers’ Guild for arbitration and emailed Reilly’s agent, warning: “Moving forward with an arbitration puts your client at significant financial risk and also destroys any remaining relationship or support that your client would receive from me and my associates in the industry.”

The AWG found against Wilson’s claim, allowing her to only claim an “additional writing” credit for the film.

The court will hear Wilson’s anti-Slapp motion and the producers’ request for a stay in proceedings on 21 November.