Mrs. Plum raised her two daughters Jamie and Jennie to be witches as well. According to Jamie, Mrs. Plum taught her daughters three important things for looking out for themselves: always look your best, never get attached to a man and to make their murders look natural so as to not attract hunters.
Around 2018, Mrs. Plum died of unknown causes and Jamie and Jennie sought to resurrect their mother. To this end, the sisters made a deal with Rowena MacLeod to steal the Black Grimoire to use a spell within to resurrect Mrs. Plum. Using a love spell, Jamie and Jennie managed to steal the grimoire from the Winchesters, but were double-crossed by Rowena who aided the Winchesters when they ran off with the book.
As a result of not totally understanding the writing in the Black Grimoire, Jamie and Jennie "winged" the resurrection spell for Mrs. Plum. As a result, she came back as a zombie rather than fully resurrected. When Rowena arrived and insulted them, the Plum sisters revealed their zombified mother with Jennie suggesting that her state was "maybe" the first step to a full resurrection. Having encountered zombies before, Rowena tried the repelling spell on Mrs. Plum to no effect. Jamie reveals that as a side-effect of the spell, Mrs. Plum is now magic-proof.
Terrified, Rowena flees into the kitchen followed by Mrs. Plum who Jennie states intends to eat Rowena's brain. Though Rowena locks herself in the room, Mrs. Plum quickly begins attempting to break down the door. As Mrs. Plum began to break through the door, Rowena desperately offered to help bring her back to life for real, but Jamie and Jennie reject her offer.
As the Winchesters arrive and fight Jamie and Jennie, Mrs. Plum breaks through the door and Rowena tries to hold her off with a chair. Rowena desperately calls out to the Winchesters that magic won't work on Mrs. Plum and asks for suggestions. Dean orders Rowena to try shooting Mrs. Plum in the head, just before Mrs. Plum flings Rowena to the ground in the living room and attempts to bite her. As they struggle, Rowena manages to grab Dean's gun off the floor nearby and shoots Mrs. Plum through the head, killing her again.
Powers and Abilities
As a witch
- Witchcraft - In life, Mrs. Plum was a witch with presumably powerful abilities. Jamie described her mother as an amazing witch and credited her for teaching everything she and her sister knew about magic.
As a zombie
- Immunity - As a zombie, due to the nature of the spell that resurrected her, Mrs. Plum was immune to magical attacks.
- Super Strength - As a zombie, Mrs. Plum was superhumanly strong, able to break through a wooden door with relative ease.
- Extreme Brain Damage - As a zombie, Mrs. Plum was vulnerable to being killed by damage to her brain, particularly being shot in the head.