Fashion rules are made to be broken.

The Cannes Film Festival is famous for its strict dress code, but this year’s red carpets have been marked by dangerously plunging necklines, high-slit skirts and see-through gowns galore.

According to the event’s charter, which got a headline-making update last year, “nudity is prohibited on the red carpet, as well as in any other area of the festival” for “decency reasons.” 

Additionally, the festival no longer permits “voluminous outfits, in particular those with a large train, that hinder the proper flow of traffic of guests and complicate seating in the theater.”

But many have ignored the new rules.

For instance, Kristen Stewart — who once protested the event’s notorious ban on flat shoes by walking the red carpet barefoot — has long been known to go sheer at Cannes, and this year’s been no different.

The “Twilight” icon posed at the “Full Phil” photo call last weekend wearing a transparent Chanel skirt set that, at first glance, made it appear as though she was wearing absolutely nothing underneath.

Her stylist, Tara Swennen, shared with Vogue that Stewart actually had on a skin-toned tank top and shorts, making the look seem “more revealing than it was.”

Riley Keough opted for a similarly sheer ensemble for the “Histoires Parallèles (Parallel Tales)” premiere, also from Chanel: a midi skirt and cardigan that let her lacy lingerie play peekaboo.

Several stars have been daring to bare in crochet styles, skin fully visible beneath the woven fabric.

Stewart opted for a red-and-black knit Chanel gown for the “Full Phil” premiere — and paired it with sneakers, another Cannes no-no.

Marion Cotillard plucked another openwork dress from the French fashion house (this one in all black with visible briefs beneath) for the evening screening of “Roma Elastica,” while jury member and director Chloé Zhao selected a sheer black lace Gabriela Hearst gown trimmed with fluttery ruffles for the festival’s opening ceremony.

And Bella Hadid paid sartorial tribute to Jane Birkin in a Schiaparelli Haute Couture gown that featured not only revealing embroidery, but also a deep neckline that plunged down to below the supermodel’s navel.

As for the trains — a tripping hazard that makes it harder for everyone to move around the red carpet at the same time — Demi Moore isn’t letting that rule dictate how she dresses.

At the “La Vie D’Une Femme (A Women’s Life)” screening, the jury member chose a lilac chiffon Gucci gown that was sheer from the thighs down, complete with a yards-long layered skirt that blew dramatically in the Riviera breeze as she made her way down the step-and-repeat.

When it comes to the year’s most glamorous film festival, it would appear, stars aren’t letting a pesky dress code get in the way of a fashion statement.