|Location/Owners||Men of Letters Bunker|
|Episodes|| 12.11 Regarding Dean|
13.12 Various & Sundry Villains
13.21 Beat the Devil
The Black Grimoire is a powerful tome of Druidic magic. The spell book has been in the possession of the Loughlin family, who would take on witches they deemed worthy to study its secrets with the family, for a price. The book makes use of ancient Celtic glyphs and is written in ancient Druidic, so that only the most old and powerful of witches are able to decipher its contents.
After retrieving the body of Gideon Loughlin, his brother Boyd prepares his body in their study while his sister Catriona retrieves the Black Grimoire, opening it to a resurrection spell. Some time later, after Sam is incapacitated and captured by the remaining Loughlin siblings, Boyd prepares the spell. Bleeding into a bowl, he tells Sam he plans on swapping out Sam's soul for his brother's, bringing him back to life. Sam is able to break free from his restraints and attack Boyd in an attempt to kill him, but Boyd is later killed by Dean after Sam chases after him. Rowena is later seen attempting to take the Black Grimoire for herself after using it to reverse the memory spell Gideon cast on Dean, but Sam convinces her to give the book to him and leave.
The Plum sisters, Jamie and Jennie, place a love spell on Dean and have him retrieve the Black Grimoire from the Bunker. At the Bunker Dean tells Sam he has fallen in love and wants to give the Black Grimoire to Jamie as a gift, believing it is cosmic fate that she asked for it. Sam attempts to protest but Dean punches him and walks back to the market parking lot, where he hands the book over to Jamie. As she is about to kill Dean, Sam arrives; his attempts to get the book back are thwarted by Dean he begins fighting Sam, until the arrival of Rowena, who separates the two and destroys the hex bag controlling Dean.
At the Bunker Rowena reveals she placed a tracking spell on the Black Grimoire before she handed it over to the Winchesters, and needs it to remove the binding spell the Grand Coven placed on her which has been limiting her magic.
The Plum sisters attempt to use the book to resurrect their deceased mother, using the soul of a stock boy. The sisters are only able to complete the first step of the ritual, bringing their mother back as a zombie, impervious to magic. When Rowena tracks them down, and upon Rowena insulting their abilities, the sisters sic their zombie mother on her. The Winchesters soon arrive and in the ensuing fight, Rowena places an Impetus bestiarum spell on the sisters, forcing them to kill each other while using Dean's gun to kill the zombie with a headshot. In the aftermath Rowena begs the Winchesters for the spell so she won't be helpless against Lucifer when he returns. Sam, understanding the fear Rowena has after her last encounter with Lucifer, tears the spell page out and gives it to her.
In hotel room, Rowena sits in a pentagram, reciting the spell from the Black Grimoire. She takes a blade and cuts down her neck, releasing a purple energy which reveals the binding spell covering her body. One by one the bindings break, returning Rowena to her full power.
After Lucifer's departure leaves the portal to Apocalypse World without a power source, Rowena muses out loud about leaving the Bunker with the Black Grimoire, but she somehow convinces herself to stay and begins going through the book to look for a way to keep the portal open.
Through the Black Grimoire, Rowena is able to channel her considerable power and keep the rift to Apocalypse World open long enough for all the refugees to cross over.