In 1919, Myrtle Tully, recently returned to America from serving as a "Hello Girl" in Europe during World War I, takes a job as assistant librarian at Adelaide College in Booker Falls, Michigan. The discovery of a cache of letters received by a student who held the same position Myrtle now holds, Yvette Sinclair, shortly before she was found strangled to death in the same library some twenty-eight years earlier, a crime never solved, sets Myrtle off on a quest to uncover the killer's identity. Information she finds results in the trial and conviction of Yvette's boyfriend at the time. But Myrtle is not convinced he is guilty. Further investigation eventually results in Myrtle's life being put in jeopardy by the real killer.