In May, Fan Bingbing, one of China’s most famous actresses, turned heads when she walked the red carpet at the Cannes Film Festival wearing DeBeers jewelry and a mint green gown by the Tunisian fashion designer Ali Karoui.

And then, the 37-year-old A-lister with an estimated net worth of US$40 million, mysteriously disappeared.

Best known internationally for her role as Blink in 2014’s “X Men: Days of Future Past,” Fan hasn’t been seen publicly since July 1, when she visited a children’s hospital in Tibet. Her absence has also been noted by her 62 million followers on Weibo, China’s main microblogging service, where her account was last active in late July.

The vanishing of the actress, whose face has adorned advertisements for luxury brands from Cartier to Mercedes-Benz to Moët & Chandon, has fueled a wave of speculation in recent weeks that she ran afoul of Chinese officials amid a government probe into tax compliance in the entertainment industry.

Fan’s troubles appear to have started back in late May, when Cui Yongyuan, a retired state television anchor, posted two of her alleged contracts for an upcoming film to Weibo. In the contract reported to the tax authorities, Fan’s salary is listed as $1.6 million. The other appeared to show an actual payment to Fan of $7.8 million.

Yongyuan said this was a clear exhibit of so-called “yin and yang” contracts that are widespread in many industries across China as a way to avoid paying taxes. China’s Communist Party has recently begun a crackdown on the practice in the entertainment industry and has expressed concern that China’s elite celebrities are “fostering money worship tendencies” and “distorting social values.”

Fan’s production company denies any wrongdoing, according to the Associated Press.

Chinese officials have not said whether Fan is under investigation or commented on her disappearance. In the past, the Communist Party, which possesses ultimate control over what content is released, has blacklisted Chinese celebrities who they believe have broken the law.

The mystery deepened last week, when the state-affiliated think tank Chinese Academy of Social Sciences and the Beijing Normal University ranked Fan last out of 100 celebrities in their annual “Social Responsibility Report.”

The actress, who was named one of Time magazine’s 100 most influential people in 2017, received the lowest possible score of zero per cent.

With files from The Associated Press