NOTE: This guide refers to Bittersweet by Miranda Beverly-Whittemore, the Penguin Random House LLC edition, Copyright 2014

Mabel Dagmar is a scholarship student who attends a prestigious East coast college where she feels out of place with her wealthy roommate, Genevra "Ev" Winslow. Mabel is surprised when Ev invites her to spend the summer at her family's compound of cottages, Winloch, on Lake Champlain in Vermont. Mabel jumps at the chance to go for two reasons. First, she will experience an amazing summer. Also, she will be able to avoid returning to her dysfunctional family in Oregon.

Each sibling in the Winslow family inherits a cottage at Winloch and Ev's is called Bittersweet. After arriving, Mabel feels as though she has been transported to a place of opulence and ease. She yearns to become one of the Winslows. Winloch was established by Ev's great-great-grandfather. It grew to 30 cottages all inhabited in the summer by Winslow family members. Mabel is in awe of Ev's parents, Birch and Tilde. She soon learns more about Ev's siblings, Athol, Benning, Galway, and Luvinia. Galway is the Winslow family misfit because of his work at an immigration advocacy group in Boston. He and Mabel start a summer fling.

Ev's elderly aunt, Linden "Indo," spurs Mabel to dig into the Winslow family secrets in exchange for inheriting her cottage when she dies. Mabel not only discovers how the Winslow family prospered when others struggled desperately during The Great Depression, she also learns some unsavory facts about Birch.

A history of murder, rape, theft, and more unite the Winslows, and Mabel brings it all to the surface.