Katherine Schneider’s life as a dentist in 1913 New York is upended when a patient reveals details of a deadly plot while under the influence of laughing gas. As she is plunged into danger, she seeks help from the dashing Lieutenant Jonathan Birch, a police officer she has long admired from afar.

Jenny Summerlin is struggling to save her dying orange grove when a baffling mystery upends her world. A skeleton buried with a priceless treasure has been found on her land, which brings of flood of investigators onto her property to study a decades old crime. Captain Wyatt Rossiter is charged with solving the puzzling discovery. Unfortunately, he is also the man who broke Jenny's heart two years earlier. Plagued with regrets and unresolved feelings for Jenny, Wyatt resists getting drawn back into her world, but he cannot rest until he solves the unusual crime.

The year is 1901, and the hustle and bustle of the holidays is descending on New York's Fifth Avenue. For the first time in her privileged life, Adelaide Forsythe couldn’t be happier about the prospect of a quiet Christmas. That’s not to say her transition from Missto Mrs. has been without challenge. Though she doesn’t regret marrying for love instead of wealth, she feels woefully unprepared to run her own household. Then, on the first Sunday of Advent, winter winds bring surprising change, first through a young orphan boy and then a seasoned housekeeper who seems too good to be true.

In 1931, the creation of the new Great Smoky Mountains National Park threatens Rosie McCauley’s home. Rosie vows the only way the commission will get her land is if they haul her off in a pine box. When a compromise offers her and her disabled sister the opportunity to stay for Rosie’s lifetime, her acceptance sets her apart from the other mountain folk. And the bond she’s forming with ornithologist and outsider Benton Fuller only broadens the rift. Eighty-five years later, Kieran heads back to the national park to find answers to her great-grandmother’s mysterious death.

Left with an estate on the brink of bankruptcy after their father's death, Lady Marigold Fairfax and her brother open a private investigation firm marketed to the elite . . . to spy on the elite. Dubbed The Imposters, Ltd., their anonymous group soon becomes the go-to for the crème of society when they want answers delivered surreptitiously. But the many secrets Marigold learns about her peers pale in comparison to her shock when she and her brother are hired to investigate her best friend's father as a potential traitor.