Becca Jo Cartwright, a spirited young woman raised on a Texas ranch, spends her days driving a pickup truck and carrying a sidearm, all while striving to become a champion bull rider. Her life takes a supernatural turn after she fends off a harasser in an alleyway with gunfire—only to watch the assailant dissolve into a mist of black smoke. Burdened by the ranch's mounting debt, she enters into a three-month contract with Lucien, a three-hundred-year-old vampire lord, agreeing to pose as his fiancée to drive away the mother who is pressuring him to marry. No one suspects that Becca carries the bloodline of a vampire hunter. Her true identity is eventually revealed as she breaks a voodoo curse afflicting her younger brother, battles a pack of besieging werewolves with a silver candlestick, and forges a holy silver blade to save a poisoned Lucien. When faced with pressure from pureblood aristocrats and the exorcism authorities, she asserts her family lineage to stand her ground. Yet, when Lucien finally kneels to confess his love, the free-spirited Becca has only one demand: a higher fee for the contract.