The young girl Beth Slocum (Aubrey Plaza) was bitten by a venomous snake while relaxing in the wild and died of poison. This incident made Beth's boyfriend Zach (Dane DeHaan) miserable and unable to get out of grief for a long time. One day, when he went to Slocum's house early in the morning, he was surprised to see Beth. Beth's father Maury (John C. Reilly) tried to cover up, but he couldn't stop Zach, who was almost crazy and tortured by love. The two lovers who were once separated by life and death met again, and their affection was stronger and like glue. But as time passed, Beth's body showed all kinds of strangeness. Her skin was pale and festering, her mood became extremely unstable, and she had incredible destructive power. Zach gradually felt scared and tried to escape from Beth. At the same time, the town also showed an unprecedented weird appearance...