The gauntlet that is Paris Fashion Week provided many a savvy star with a reason to step up her game. The best dressed delivered classic with a modern twist, made a strong case for orange and, in general, looked ineffably fresh. The ones who failed offered the precise opposite: stuffy, granny-style frump.

Dianna Agron

For her front-row appearance at Louis Vuitton’s Paris show, Agron aced color dissonance, combining a chic LBD with a purple striped coat, Barbie-pink bag and wine-toned boots (all by LV).

Dakota Johnson

At the Christian Dior show in Paris, the “Fifty Shades of Grey” star donned an exquisitely simple tailored ensemble, courtesy of the house. It’s a fashion-forward take on a traditional tuxedo dressing, rife with all the off-the-shoulder grace of a modern-day “Madame X.”

Hailee Steinfeld

Joining Johnson at Dior was Hailee Steinfeld, who reminded us of her preternatural fashion intelligence in another head-to-toe look by the brand. Orange is usually a color to approach with skepticism, but this slick get-up gives us reason to believe.

Lady Gaga

The orange memo went straight to Gaga’s head. The singer pulled off fire-hued locks in Paris, where she scaled back her typical drama in a sophisticated Martin Grant jumpsuit.

Giuliana Rancic

The host turned up to the Astra awards (anyone?) in Sydney, Australia, in a mind-bogglingly bad department-store number, illustrating — once again — the absurdity of the fact that she gets a paycheck to critique fashion.

Helen Mirren

We love Helen Mirren, but this funeral garb she wore to the Broadway opening of her show “The Audience” is making us quite sad.

Nicole Richie

At a West Hollywood bash, Richie presented a case of conflicting ideas that demands swift resolution. Are you a wild, pink-haired pixie, Nicole, or a prim, tight-collared coquette? Figure it out quickly — this look is making us queasy.

Salma Hayek

It’s not that Ms. Hayek must always flaunt the curvaceous shape for which she’s known, and as far as outfits go, there have been worse than this matronly dress/blazer/pantyhose situation she wore to a film screening in London. Still, the whole thing reads stiff, austere and uncomfortable — and there’s nothing appealing about that.