Uh oh...look out, Rose McGowan. Asia Argento says she's coming after you with a libel lawsuit from the fancy London law firm that represented the late Princess Diana in her divorce from Prince Charles.

Argento, the #MeToo warrior who has declared war on her former friend and fellow fighter in the anti-sexual harassment movement, tweeted another threat Tuesday, warning McGowan to expect to hear from her lawyers at Mishcon de Reya soon.

And McGowan's current squeeze, model Rain Dove, has been added to Argento's legal hit list:

"The 24hr deadline given to retract your recent false statements about me has now passed. I must inform you & @raindovemodel that I’ve instructed Mishcon de Reya to seek substantial damages for deception, fraud, coercion and libel. You will hear from them shortly," Argento's tweet said.

Mishcon de Reya, which has an office in New York, is more famous in Britain as the firm that represented Diana in her 1995 divorce from the Prince of Wales. (She got millions, inherited by her sons, Princes William and Harry, after she was killed in a Paris car crash in 1997.)

The firm confirmed they've been retained (or "instructed," as British lawyers put it) by Argento but declined to say anything else about the case, according to spokeswoman Hayley Geffen.

Mishcon de Reya would be Argento's third set of known lawyers since the scandal over Jimmy Bennett erupted Aug. 19 with a story in The New York Times revealing that Argento and her late boyfriend, Anthony Bourdain, had agreed to a $380,000 payoff to Bennett, the former actor who once played her son in a movie.

However, the Italian actress' use of a British firm to sue an American actress may suggest her threatened libel lawsuit will be filed in Britain, where it is easier to pursue libel and defamation claims than in the United States.

Argento is mighty peeved at McGowan and Dove because they have made clear in public statements that they take the side of Bennett who says he and Argento had sex when he was 17 and she was 37 in 2013. If true, that would be a crime California where the age of consent is 18.

Argento first strongly denied a sexual encounter. Then Dove released private texts from her in which she seemed to admit it. Then Argento issued another statement accusing Bennett of rapingher. This claim was undermined by the publication of a picture of the two of them, apparently naked and looking happy, in bed together on the date of the 2013 encounter in a Los Angeles-area hotel room.

Thus, the falling out between the two former friends. On Monday, Argento fired her first tweet-shot at McGowan.

"It is with genuine regret that I am giving you 24 hours to retract and apologise for the horrendous lies made against me in your statement of August 27th. If you fail to address this libel I will have no option other than to take immediate legal action," Argento's tweet read.

So far, McGowan has not responded directly to Argento's legal threats but a tweet she posted Monday could have been a comment on her situation even though it was ostensibly about the current controversy delaying Supreme Court nominee Brett Kavanaugh's confirmation, regarding a decades-old allegation of attempted rape.

"Sexual assault is a crime and every allegation should be thoroughly investigated," the tweet began.

"my sentiments exactly," McGowan added.

Argento is threatening McGowan because the latter publicly urged her to "do the right thing" regarding Bennett, and because she framed Argento's responses to the scandal so far as a potential threat to the reputation of the #MeToo movement.

Both McGowan and Argento have been leaders in the movement because they were among the first to publicly accuse movie mogul Harvey Weinstein of rape, thus leading to his downfall and the surge of the culture-changing movement to call out sexual harassment and assault in workplaces.

Now their dispute over Argento's encounter with Bennett, now 22, threatens to render them too busy fighting each other in court to continue leading the movement.

Lawyers and publicists for both actresses have not returned messages from USA TODAY.

The Los Angeles Sheriff's Department has said it is looking into the matter of the Argento-Bennett encounter but has not said whether anyone will be charged.