Set in the mid-1930s, Filthy Sugar tells the story of Wanda Whittle, a nineteen-year-old dreamer who models fur coats in an uptown department store, but who lives in a crowded rooming house with her hard-working widowed mother and shrewd older sister, Evelyn, in the "slums" behind the city's marketplace; a world where "death is always close but life is stubborn." Bored with the daily grind and still in shock from the sudden death of her father, Wanda finds both escapism and inspiration in the celluloid fantasies of the Busby Berkeley musicals, Greta Garbo dramas, and Jean Harlow sex comedies. Strutting up and down the aisles of Blondell's department store, her peep-toe high heels drumming out a steady beat on the waxed linoleum floors, Wanda fantasizes that she's Ruby Keeler, the tap dancing sweetheart from 42nd Street. But Wanda wants more than to wear a glamourous woman's coat-she wants to live inside of her flesh.

Her dreams come true after a chance encounter with the mysterious Mr. Manchester, proprietor of the Apple Bottom burlesque theatre. Suddenly Wanda is thrust into a world of glitter and grit. Descending from the rickety, splintered roof top of the Apple Bottom theatre on a red velvet swing, Wanda Whittle morphs into a dream named Wanda Wiggles; sweeter than a strawberry sundae and tastier than a deep dish apple pie. At the Apple Bottom she meets Lili Belle, a naughty cartoon flapper brought to life; Queenie, a sultry headliner whom Wanda feels drawn to like a bee to a butterfly bush; the sweet and salty Eddie, a drummer who thumps out his words like bullets from a machine gun and Brock Baxter, the Apple Bottom's vaudevillian comic whose apple cheeked, pretty boy exterior belies his sinister intentions.

All will have an impact on Wanda's journey. Cowardly boxers, shady coppers, dime store hoodlums, and painted ladies-Wanda will encounter them all! On her voyage from rags to riches and back again, Wanda experiences a sexual awakening and achieves personal independence as she discovers that a girl doesn't need a lot of sugar to be sensational!