Finley and Betty's close friendship survived Fin's ninth grade move from their coastal Maine town to Manhattan. Calls, letters, and summer visits kept them close, and in the fall of their senior year, they both applied to NYU, planning to finally reunite as roommates. Then Betty disappears. Her ex-boyfriend Calderadmits to drowning her, but his confession is thrown out, and soon the entire town believes he was coerced and Betty has simply run away. Fin knows the truth, and she returns to Willistonforone final summer, determined to get justice for her friend, even if it means putting her loved ones - and herself - at risk. But how much is she willing to damage to get her revenge and learn the truth about Betty's disappearance, which is more complicated than she ever imagined - and infinitely more devastating?