Exploring The Forbidden Knowledge Of 'Doctor Strange': What Is The Book Of Cagliostro?

In Doctor Strange, the library of Kamar-Taj is home to countless ancient books, tomes that unlock the secrets of the universe. But some of those books, collected by the Ancient One herself, are forbidden; they are chained, and watched over by the librarian — Wong — with the greatest of care. One of those forbidden books is called the 'Book of Cagliostro', and the whole Doctor Strange movie essentially hinges on a couple of pages from this book having been torn out!

WARNING: MAJOR SPOILERS FOLLOW!

The Book of Cagliostro in Doctor Strange

We're introduced to the Book of Cagliostro as a forbidden tome; one that holds dark power that only the Ancient One knows of. Naturally, Stephen Strange — blessed with a photographic memory and an innate ability to join the dots — is unable to resist the lure of forbidden knowledge.

We learn that the Book of Cagliostro contains spells that enable a sorcerer to tap into the Dark Dimension itself. This is the secret of the Ancient One's long life; she has chosen to use Dormammu's own power against him. Unfortunately, Strange wasn't the first one to deduce this; Kaecilius worked it out as well, and saw the Ancient One as hypocritical for withholding the power to conquer death from her followers. He became fascinated with the idea of conquering death, and used pages from the Book of Cagliostro to commune with the Dark Dimension itself.

The Book of Cagliostro also seems tied to the Eye of Agamotto, in that it contains guidance on how to use the Eye to manipulate the flow of time. These spells are desperately dangerous, and run the risk of fracturing reality itself; they're also absolutely crucial, in that they give Doctor Strange his chance to outsmart Dormammu. Given that the Eye of Agamotto is traditionally associated with a Sorcerer Supreme (in the film, as in the comics, Agamotto was the first Sorcerer Supreme), this raises some intriguing questions. Was the Cagliostro of the MCU a Sorcerer Supreme? I suspect not; the rest of the Book of Cagliostro seems to tamper with knowledge that the Sorcerers Supreme would refuse to risk toying with. More likely is the possibility that he was somehow associated with a Sorcerer Supreme (trained by one?), and stole the Eye of Agamotto from them in order to experiment with it.

We're told that the warnings come after the spell, but that comment in itself is fascinating. You only put in warnings when you learn what can go wrong the hard way; is it possible that Cagliostro used the Eye of Agamotto, and accidentally fractured reality? If that is the case, then either Cagliostro himself or the Sorcerer Supreme of his time must have repaired the damage, and the warnings were then noted by Cagliostro in his tome.

In the Real World

Believe it or don't, Cagliostro is actually a historical figure! Count Alessandro di Cagliostro was a French 18th-century occultist whose history is shrouded in legend. Cagliostro showed his character even as a youth, when he manipulated a wealthy goldsmith to pay him for 'hidden treasure' and savagely beat him before stealing the silver he'd been paid. While traveling through Sicily, he met his beloved wife Lorenza Seraphina Feliciani (although he seems to have loved her, he wasn't above trading her sexual favors for knowledge he sought).

We may have forgotten the name of Cagliostro, but he became something of a household name at the time. In fact, at one point he was recommended as a physician for Benjamin Franklin! Ultimately, Cagliostro's reputation fell into disrepute; he was exiled from France due to suspected involved in a major theft, and upon returning to England was accused of his childhood crime. Visiting Rome, Cagliostro fell foul of the Inquisition, and was imprisoned as a Freemason. Some accounts actually suggest that his wife betrayed him; whatever the truth may be, he died in jail.

Cagliostro is actually an important man in the history of Occultist movements. He was key in the spread of Freemasonry, establishing the Egyptian Rite of the Freemasons and opening lodges all over Europe. He was also known to have collected esoteric knowledge, such as the Most Holy Trinosophia, which details many kabbalistic, alchemical and masonic mysteries.

The Comic Book Version

Naturally, Marvel Comics has been unable to resist the temptation to use such an intriguing historical figure! In the comics, Cagliostro was reinvented as an 18th-century sorcerer who became fascinated with the quest for eternal life. As in the MCU, he compiled a book — one that comes from three sources:

• Cagliostro's own studies. Questing for immortality, he learned many dark secrets, and recorded them in his book.
• Notes from a time-traveling sorcerer. At one point in his life, Cagliostro was in fact replaced by a time-traveler called Sise-Neg. When Cagliostro resumed his own identity, he discovered Sise-Neg's notes on the manipulation of time, and used them as part of his book.
• Pages copied from the Darkhold. A legendary book of spells that predates humanity itself, the Darkhold is one of the most dangerous mystical tomes in existence.

As you can see, the Book of Cagliostro in the MCU is very similar to the one we see in the comics — concerned with both the secret of eternal life (Cagliostro's obsession) and the manipulation of time (Sise-Neg's obsession).

Wait, Isn't the Darkhold in Agents of S.H.I.E.L.D....?

Yes! The Darkhold itself is becoming the A-plot of Agents of S.H.I.E.L.D. Season 4! The forbidden knowledge of the Darkhold has been revealed as a source of fascination for classic Hydra agents ranging from the Red Skull himself to Daniel Whitmore. Spells from the Darkhold were responsible for the creation of the 'ghosts' currently plaguing S.H.I.E.L.D., and Agent Coulson and his team are on the hunt to find the so-called 'Book of Sins' before the 'ghosts' do. Unfortunately, they're already too late; Episode 5, "Lockup", already started with the 'ghosts' discovering this dangerous book of magic. Thankfully, we learn that the Darkhold only reacts to living flesh, but that's clearly only holding the darkness back for an episode (or two at the most).

I'm happy to assume that, as in the comic book universe, the MCU version of the Book of Cagliostro is also derived from the Darkhold in Agents Of S.H.I.E.L.D. That means that Coulson and his team are dabbling in the kind of sorcery that the Ancient One considered forbidden from all but herself — what could possibly go wrong?!

Ultimately, the Book of Cagliostro is a fascinating but subtle tie between Doctor Strange and Agents of S.H.I.E.L.D.. It also hints at a lot of dangerous secrets in the Ancient One's past, ones that could easily come back to haunt Doctor Strange in the inevitable sequel. It's a minor continuity detail, but it's nice to see Doctor Strange pull even the most obscure aspects of comic book continuity into the MCU.