The opening day could be overshadowed by the arrival of the verdict in Gerard Depardieu's sexual assault trial.
The international star of French cinema, 76, was found guilty of assaulting two women on a film set in 2021.
The issue of sexual violence in the film industry is a hot topic - a French parliamentary inquiry criticised "endemic" abuse last month, while on Monday screen legend Brigitte Bardot defended two accused actors, including Depardieu, saying they should be allowed to "get on with their lives".
Those aren't the only external events that will make their presence felt on La Croisette.
Film stars and industry deal-makers may also have a word or two to say on the red carpet about US President Donald Trump's plan to impose 100% tariffs on foreign-made films.
French Culture Minister Rachida Dati recently said the imposition of any such tariffs would lead to "the American industry being penalised, not ours".