Nan Astley (Rachael Stirling) is a young girl, working as a cook and waitress in her family's seaside restaurant. When she meet Kitty Butler (Keeley Hawes), a male impersonator, her life changes. She quickly finds herself falling in love with Kitty. Nany follows Kitty to London, and things are going quite well there until Kitty finds a marriage of convenience and consequently breaks Nan's heart. Nan becomes a street walker, and eventually meets Florence (Jodhi May) and her brother Ralph (Hugh Bonneville). Nan and Florence begin a relationship, and then Kitty comes back into Nan's life, trying to rekindle their old flame. Will Nan stay with Florence, or will she go back to her first love, Kitty?