When country girl Sidonie-Gabrielle Colette (Keira Knightly) marries a charismatic egomaniac named Willy (Dominic West), he unlocks the door to the tantalizing artistic world of the Paris literacy scene. With her creative appetite sparked, Willy has Colette write novels under his name. The phenomenal success of her Claudine series makes Willy famous and elevates them both to the high life.
Although she is now the toast of the town, the lack of recognition begins to gnaw at Colette. In turn, their marriage starts to internally combust, fueled by Willy's infidelities and Colette's growing interest in women, and the gender defying Missy (Denise Gough). On a downward spiral, Willy resorts to increasingly desperate measures to pay his debts and sabotage his wife, but Colette is developing resources of her own.