Warning! Major SPOILERS for WandaVision below.
Although Wanda created the alternate reality encapsulating the town of Westview, some things are still a surprise to her – such as a mysterious magic book she discovers in Agnes’ basement. WandaVision episode 7 ended with the twist that nosy neighbor Agnes is really ancient sorceress Agatha Harkness, and the bad things happening in Westview have been “Agatha All Along!” Wanda stumbled onto this discovery when she found herself exploring Agatha’s house for the first time.
“Breaking the Fourth Wall” sees Wanda taking a one-day break from after she lost control and expanded the boundaries of the Hex. In order to give her some much-needed me time, “Agnes” takes Billy and Tommy off Wanda’s hands. Later in the day, Agatha lures Wanda to her home and into the basement. Right off the bat, it’s obvious that the basement is like nothing like anything Wanda created in Westview.
The dark and sprawling chamber is a far cry from the picture-perfect sitcom reality that Wanda conjured up, and the show’s aspect ratio notably shifts when she enters it, indicating that she’s back in the “real world.” Among the arcane accoutrements in Agatha’s basement is a weathered book glowing with strange magical energy. But what is this book, and what does it do?
Quite a few magical books have made their way through the Marvel comics, meaning that the book in Agatha’s basement could be one of many. However, there are a few frontrunners for the identity of the mysterious book. One of the top contenders is the Necronomicon, which was an ancient book containing black magic created by Abdul Alhazred, the Mad Arab. Spells in the book allowed the conjurer the power to summon demons. The Necronomicon was created in the 8th century but was banned for centuries, which made it something of a legend in certain circles. Copies of the book eventually fell into the hands of Wanda, Agatha, and even Doctor Strange.
The Necronomicon was said to be based on the Darkhold, which is also another possibility for the book in Agatha’s basement. According to Marvel lore, evil Elder God Chthon wrote his evil works and spells onto an indestructible parchment. Those pages were eventually bound together in the book that became known as the Darkhold. Chthon left the scrolls on earth so they could always serve as a conduit for his influence and power. The Darkhold has a long and storied history, spanning all the way into the 21st century. Marvel characters have taken advantage of its spells over the years – one of which includes the ability to control the will of others, which falls in nicely with the events of WandaVision.
While the Necronomicon and the Darkhold are two of the most likely contenders for the book in Agatha’s lair, there are a few other options. One is the Tome of Zhered-Na, which was created by sorceress Zhered-Na. The sorceress combined all of her magical scrolls in a tome that was considered one of the most powerful books of magic ever created. There’s also the Book of Cagliostro, which came from the Ancient One’s private collection. The book focused on the dark side of the mystic arts, which seduced many of her students in losing their way completely.
The reason for the magic book being in Westview may be hidden in episode 7’s commercial. Every episode of WandaVision features a cryptic ad break revealing a nugget of trauma from Wanda’s past. “Breaking the Fourth Wall’s” was one of the most telling of all, as it may have revealed why the book is in Westview. The commercial is for a fake drug called Nexus, which is described as “a unique antidepressant that works to anchor you back to your reality – or the reality of your choice.” This appears to be a clear reference to a phenomenon from Marvel Comics called the Nexus of All Realities.
The Nexus is a cross-dimensional gateway that (as the name suggests) provides a pathway to all realities within the multiverse. Multiple realities have firmly existed in Marvel Comics for years, but have only been alluded to thus far in the MCU. Marvel has confirmed that the MCU Phase 4 will explore the multiverse and the book in Agatha’s basement may very well be the thing that cracks it open. Judging by the looks of her basement, it looks as if Agatha’s lair was present long before the town of Westview, New Jersey. That means the book’s arrival in Westview likely predates Wanda’s. Just like the powerful women of Westview, the book exudes a colorful glow and is clearly full of some powerful, ancient magic. All of that combined with the introduction of the Nexus hints that Agatha’s book is a portal to the multiverse.
“Breaking the Fourth Wall” reveals that Agatha has been manipulating Wanda for the entire first season of WandaVision. The question still remains why, but it’s clear that Agatha’s intentions are nefarious. Agatha intentionally lured Wanda to her lair, because the time was right to reveal the next phase of her plan. As that book in her basement clearly contains powerful magic, it’s safe to assume that Agatha plans to use that against her. The episode’s post-credits scene shows Monica discovering Agatha’s basement, only to reveal that her eyes were glowing purple. That happens to be Agatha’s signature color, meaning that Monica has fallen under Agatha’s spell. Due to her mischievous nature, Agatha may use the magic in her book in order to get Monica to do her dirty work and fight Wanda.
If Agatha’s book is a magical portal, she may end up using it to summon the demonic big bad, Mephisto – Marvel’s version of the devil. WandaVision has subtly included lines like, “The devil is in the details” and “Unleash hell, demon spawn,” and planted 666 in the background of various scenes, all pointing to something devilish working behind the scenes of Westview. But the most telling reference to Mephisto comes in form of the arrival of Wanda’s twin boys. In the comics, Wanda uses fragments of Mephisto’s soul to create her boys. However, the villain eventually reabsorbs the boys. “Breaking the Fourth Wall,” ends with Wanda realizing her boys have gone missing after Agatha offered to babysit. That might very well be a hint that Mephisto is on his way.
With the villainous Agatha reveal, it’s not out of the question that she would be in cahoots with the devil himself. Whatever magic that book holds, it’s clearly dark and powerful. Agatha may intend to use a spell in the book to summon Mephisto to Westview. At the time of writing, WandaVision only has two episodes left. So while the appearance of Mephisto may not factor greatly into the remaining plot of WandaVision, his introduction could hold great weight for the future of the MCU.