Love is in the air when a stray cat shows up at the Blue Hill Library with a diamond engagement ring attached to its collar. Anne is determined to find the cat's owner before Liddie falls in love with their new furry friend, but news of the ring brings more than one prospective bride to claim it as her own. As Anne tries to discover the truth, two handsome men vie for her attention, and she realizes she may be in danger of falling in love herself.

Meanwhile, a former writing student of Aunt Edie's, named Hope, returns to Blue Hill with an exciting request: because Edie introduced her to her fiance, Theo, they would like to get married at the library. Anne is thrilled to be involved in the culmination of Edie's matchmaking, but planning someone else's wedding turns out to be more work than she expected.