"Rosemary, Thora, and Jane lived at the end of the lane, one was thin, one was fat, and one was very plain". This is how Ellie Haskell remembers her grandmother's three friends, known collectively as "the bridesmaids". She had once asked her mother where the nickname came from and her mother replied, "It's a long story, best forgotten". Every family has its secrets. Now, thirty years later, a letter from the bridesmaids arrives informing Ellie that her grandmother, Sophia, wishes to make contact. This might have been heartwarming news but for one small detail: Sophia is dead. Ellie sets out to visit the bridesmaids on what becomes a life-changing journey that includes a seance, a hidden diary, and a murder that took place more than fifty years ago.