When Sarah Merritt arrives in Dakota Territory in 1876, she steps off the dusty Cheyenne stagecoach determined to start this ramshackle gold-rush town's first newspaper. In Deadwood, her runaway younger sister, Addie, is living and working as domestic help at Mrs. Hossiter's boardinghouse, according to her letters. Five years after Addie's flight from home, Sarah is carrying the sad news that their one remaining parent, newspaper publisher Isaac Merritt, has died.

But when Sarah - tall, prim, and nearly a spinster at 25 - sets up her father's printing press in the middle of Main Street, she finds herself at loggerheads with Sheriff Noah Campbell. Headstrong and opinionated, with an auburn mustache and grinning gray eyes, he arrests her on the spot. And so begins an enmity between two willful individuals that can change only when they find themselves united in a common goal: to reclaim the Addie whom Sarah once knew.

But life is never simple. Mrs. Hossiter is more commonly known as Rosie in this bawdy frontier town, and Addie's work is as an "upstairs girl", not an upstairs maid. Addie is furious when Sarah turns up at the bordello - and she tells her proper sister to get out. What could have happened to change Addie so - and what can Sarah do to regain the sweet sister of her youth and bring her home again?