In “Challengers,” Zendaya plays a tennis star named Tashi Duncan. Her clothes are central to her identity; the character is sponsored by Adidas and costumed in sporty-and-rich outfits by the designer Jonathan Anderson.

“She’ll have a fashion line,” one of Tashi’s suitors predicts to another in the trailer. “She is going to turn her whole family into millionaires.”

Fashion is equally important to the real-life Zendaya — a tool of both image-making and moneymaking. She has become a defining star of the modern movie press tour. Coverage of these appearances can be feverish, with thousands of articles and social-media posts produced for each stop: a premiere in New York, a photo call in Mexico City, a news conference in Seoul.

The fever rises when actors lean into thematic dressing. The cast of “Barbie” drowned themselves in pink, ripping looks straight from vintage toy boxes. The stars of “Madame Web” wrapped themselves in blingy netted gowns. Kristen Stewart wore very little to promote her erotic thriller “Love Lies Bleeding.”

Still, few can generate quite as much attention as Zendaya, who, for example, wore a vintage robot suit by Mugler to the London premiere of “Dune: Part Two” in February. (Her apparent theme for this press tour: futuristic desert warrior queen.) From this single moment, the data analytics company Launchmetrics valued the media impact for Mugler to be worth $13.3 million, according to Women’s Wear Daily.