Allie Bryant and her identical twin sister Fiona are the best of friends. Although the girls are polar opposites at school, Fiona a popular athlete and Allie an introverted scholar, they have an unbreakable bond that no one outside of their own world could understand. One terrible night, Fiona is stolen from Allie's life. Fate and poor choices cost Fiona the ultimate price. Allie is left alone to reenter the world without Fiona's support. Everything Allie thought she knew about herself, her parents, and her twin comes into question. When she discovers Fiona's hidden journal, Allie realizes that Fiona had hidden many secrets. She comes to the frightening realization that she didn't know Fiona nearly as well as she thought. The mystery surrounding her sister's life and choices weighs heavily on Allie as she journeys through her grief. Her parents' struggle makes her own pain almost insurmountable, if it weren't for an unexpected friendship Allie finds with a young man. Shaun has found peace with a similar loss in his life and helps Allie find her way through the dark. In spite of chaos and loss, Allie finds the value of family, friendship, and her own gifts. Following Allie through her first year without her sister, The Long Goodbye asks the question, how does one continue to live without the person they lived for?