Poisoning is the preference of most female serial killers and Sioux Falls, South Dakota has a poisoner on their hands. The killer's choice, belladonna, a rare flower in the United States. The use of it is nearly unheard of. Then a chance encounter; a hand gesture, the laugh, Aislinn Cain knows it's him. Her old foe has returned to torment her. The rest of the SCTU is worried her brain tumor has returned, because it's impossible. As Aislinn falls further down the rabbit hole, chasing phantoms, the team tries to pull it together to find their poisoner. However, Aislinn isn't the only one chasing phantoms, as belladonna brings back nightmares for another member of the SCTU and will leave them questioning their decision to work with serial killers. Then someone attacks the VCU, further hindering the investigation. Amid the mass deaths, the SCTU must decide between tacking down the person poisoning bar patrons in South Dakota or getting revenge for their fallen serial killer hunters. Finding this killer will bring more questions than answers, it will open old wounds, and force everyone to rethink what they know about serial killers.