SPOILER WARNING: The following article contains major spoilers for Doctor Strange. If you have not yet seen the film, and don't wish to know any details about its ending, please click away to another one of our wonderful articles, and save this one for later!
Fitting into the tradition of Marvel Studios origin films, Doctor Strange traces the narrative of the titular arrogant surgeon as he goes on a life-changing adventure that puts him on the path to become one of the most powerful superheroes on Earth. He is, however, not the only character who winds up undergoing a massive change. Playing a key supporting role, Chiwetel Ejiofor's Karl Mordo goes through a key transformation himself... and it's one that we will see important consequences from as the Marvel Cinematic Universe moves into Phase Four and beyond.
So what exactly happens with Mordo in Doctor Strange? That's exactly what we're here to discuss in this extended feature analyzing the ending of the Scott Derrickson-directed blockbuster. So strap in, and let's take a look at what we've seen from Mordo thus far, and what we can expect from him in the near and distant future!
Why Mordo Left Kamar-Taj
For years, Karl Mordo was a student at Kamar-Taj, learning in the ways of the mystic arts with The Ancient One (Tilda Swinton) as his teacher. Like Dr. Stephen Strange (Benedict Cumberbatch), he entered the Nepal training facility as a stubborn, close-minded individual - but after learning to open his mind and accept that there are elements of our universe he didn't understand, he became an incredibly powerful sorcerer at The Ancient One's side. He spent years as a loyal warrior for the forces of good in our universe -- proudly willing to take evil lives in order to spare innocent others -- but in Scott Derrickson's Doctor Strange we watch as a major revelation and an incredible abuse of power causes Mordo's faith to waiver, and for him to turn against what he formerly believed.
The first blow comes at the end of the second act, when Doctor Strange makes the unfortunate decision to reveal a dark secret that The Ancient One has been keeping -- potentially for centuries. While the Sorcerer Supreme forbade any of her followers from abusing dark magic and tapping into the power of Dormammu in the Dark Dimension, it turns out that she was actually doing it herself. Because there is no such thing as time in the Dark Dimension, The Ancient One tapped into it in order to extend her own life. It was discovering this that led Kaecilius (Mads Mikkelson) to see her as a hypocrite and seek Dormammu's power for himself -- but this was kept hidden from Mordo. When he does finally learn about it from Strange in the New York Sanctum Sanctorum, it most definitely rocks him to his core -- as he truly put all of his confidence in the ways of The Ancient One, and was very clearly disturbed to learn that she isn't the perfect force for good that she portrayed herself as.
Deeply troubled as he was after losing trust in his mentor, Mordo was still willing to fight with Strange to prevent Kaecilius from bringing Dormammu to Earth -- but it's this battle that winds up being the proverbial straw that breaks the camel's back for the green-robed sorcerer. While Mordo is more than willing to kill Kaecilius and his zealots, what he's definitely not cool with is watching his surgeon-turned-wizard ally/friend bend the rules of nature to stop the encroachment of the Dark Dimension. It's foreshadowed early in the movie that Mordo has a serious problem with Strange using the Eye of Agamotto a.k.a. the Time Stone, and it's Strange's continued abuse of the talisman that drives him away from the Kamar-Taj.
For those familiar with Karl Mordo from the comics, this is a significant deviation from the way that the character was originally introduced, as Mordo was immediately presented as Doctor Strange's arch-nemesis in the hero's second issue/adventure. For the big screen adaptation, however, the filmmakers agreed that the best way to use him would be to make him Strange's ally at first, thus giving his relationship with the protagonist more weight and meaning. As co-writer Jon Spaihts explained to us in an interview,
It's a tale that we've seen play out in dramas for centuries, as two former allies find themselves in philosophical conflict, and become enemies as a result. Over the course of Doctor Strange, the titular hero learns how magic can be utilized to help our world, while Mordo instead learns how magic can be utilized to corrupt it. It should make for some great narrative material moving forward in the Marvel Cinematic Universe.