In post-World War I London, Edith Thompson refuses to be put in anybody’s box. She has a successful professional career, and despite the custom of the time, remains childfree in her marriage to husband, Percy.

While Edith may seem as though she’s living her best life, the truth is, she’s miserably married to the dull Percy and escapes the dreariness of her marriage by gambling, dancing, and enjoying everything London Town has to offer.

But when Edith gets reacquainted with her brother’s old school chum, eighteen year old Freddie Bywaters, she is consumed by a whole new passion and in her explicit love letters to her younger lover, Edith fantasizes about getting rid of Percy – for good.

And then one night, her dreams become a nightmare that would transfix London for decades.