With its A-list cast and sumptuous belle-époque settings, you might expect this U.K. take on the origins of French writer Colette to be a handsome snore. But you’d be wrong.

Things start in 1893, with Knightley as Sidonie-Gabrielle Colette, a provincial 20-year-old with good breeding and no money. Her journey from skeptical fascination at the Parisian literary demimonde to eventual mastery of it is the core of the story and it gives Knightley one of her most rewarding roles to date.

Perhaps even more striking, especially for people used to seeing him as squishy-willed Americans in shows like The Affair and The Wire, is Dominic West’s in-depth portrayal of her peacock of a husband, Henry Gauthier-Villars, known to everyone by his frankly phallic pen name, Willy. He’s a cheating, lying bully who consis­tently spends more than he makes from his crowd-pleasing tales of urbane debauchery, mostly written by a stable of scribes he barely pays. Willy sees something in his new wife’s recollections of country life, though, and teases out the innate talent in someone who initially expresses no interest in writing.

When Gaby, as she’s initially known, comes up with a surprise hit with tales of an alter ego called Claudine—published with Willy’s byline, of course—demand goes through the roof. And the stage is set for an eventual showdown over who gets credit for what. He’s a foil for her sexual self-discovery as well, at first encouraging her interest in a red-haired patron of the arts (Eleanor Tomlinson) and then caddishly competing for the same woman’s attention.

Later in the game, she finds a supportive ally in a cross-dressing aristocrat, ironically called Missy (Juliet, Naked’s Denise Gough), who pushes her to perform in the scandalous music-hall burlesques that will eventually become the basis of worldwide success under her own name, with her own distinctive fashion profile, which actually included branded merch.

The nearly two-hour tale only hints at what’s to come. Director Wash Westmoreland and principal screenwriter Richard Glatzer have previously collaborated on projects as different as the Alzheimer’s tale Still Alice and the gentle Mexican-American Quinceañera. Here, they dig into the strange turns of fate and creative (and other) urges that contribute to developing a unique voice on the world stage. Crucially, this witty Colette never fails to entertain in its own right.