In rural West Virginia, Joanie and her foster siblings live on a farm tending a mysterious plant called the vine. The older girls are responsible for cultivating the vine, performing sacred rituals to make it grow. After Joanie's arranged marriage goes horribly wrong, leaving her widowed and with a baby, she plots her escape with the help of her foster brother Cello. But before they can get away, her baby goes missing and Joanie, desperate to find him, turns to the vine, understanding it to be far more powerful than her siblings realize.