Rx Mayhem picks up only hours after the finish of Rx Murder. Dr. Norrie Marconi is in a good place: She's solved an old friend's murder and her love life is blooming. She still has issues to deal with, such as her father's ghost and that malpractice suit, but she feels like things are settling down and she's getting her life in order. Wrong.

The senior doctor in her medical group drops a bombshell that threatens to disrupt her life, some of the patients start acting strange, and one winds up near death from multiple gunshot wounds. Then there's her father's ghost who insists he won't be free until she finds out what happened to his boyhood friend Corrado, whom he's sure was murdered. When Norrie's inquiry turns up a dark side to Corrado, she hires an eccentric psychic to free her father from the family home. And that's when things take a sharp left turn.