To escape the bitter division of loyalties in her family following Georgia's succession from the Union, Anna Kate Monroe accepts an invitation to serve as a companion to a spinster aunt in Texas. She is surprised to find herself traveling in the same direction as a handsome stranger she meets right before she begins the long train ride west; and she is even more thrilled to discover they share the same destination.Captain Gregory Armstrong has been sent undercover from Massachusetts to investigate the claim that several prominent southern families are financing a major supply route responsible for bringing a steady supply of horses, ammunition, and fighting men to the Confederate states. When his investigation leads him straight to Anna Kate's doorstep, he has no choice but to follow her and his suspicions all the way to San Antonio. To explain his presence, he pretends to be a gentleman of leisure, paying a visit to a western railroad spur as a potential investor.As the evidence against his lovely target and her family mounts, he grapples with an unexpected attraction to her that will test his mettle as both a spy and a man of honor.