Variety reported that the 21-year-old Cannes jury member fainted at the event, just as festival director Thierry Fremaux introduced actor Francois Civil onstage, when Elle collapsed and fell off her chair nearby.
Sister Dakota Fanning, who was sitting at a table next to Elle, helped her to her feet before security whisked them away.
British star Colin Firth, who was seated close-by, “quickly leapt to his feet and offered assistance to the dazed actress” and actress Marion Cotillard, “placed a hand over her heart as Fanning was taken away by security.”
Elle later took to Instagram to confirm the incident, writing, “Oops, had a fainting spell tonight in my 1950’s Prada prom dress but it’s all good!! #dresstootight #timeofthemonth”