Two years ago, Marvel Studios introduced fans to the cosmic side of the Marvel Cinematic Universe with Guardians of the Galaxy, which went on to be one of the biggest movies of 2014, despite being based on a rather obscure comic book. This year, the Marvel Phase 3 lineup continues with an introduction to the mystical and magical corner of the MCU with Doctor Strange, hitting theaters nationwide November 4. Today we have a new preview that goes behind-the-scenes of Doctor Strange, and offers more details on how Chiwetel Ejiofor's Baron Mordo fits into the story.

This new preview, which debuted on Marvel's YouTube, features plenty of behind-the-scenes footage along with interviews with executive producer Stephen Broussard and Chiwetel Ejiofor, who reveals that his character Baron Mordo is "instrumental" in Stephen Strange (Benedict Cumberbatch) being introduced to this universe, since he is "close" to The Ancient One, played by Tilda Swinton. We also hear from Tilda Swinton, and Kevin Feige, who reveals new details about the villain, Kaecilius.

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We got our first look at Kaecilius in set photos taken towards the end of production, and a prequel comic book seemed to tease that Kaecilius himself is also a Master of the Mystic Arts. While those details have never been confirmed, Kevin Feige teased that Kaecilius is part of a group of villains known as the Zealots, who become seduced by the dark magical powers they find. Kevin Feige also revealed that Kaecilius is interested in taking down the barriers between these dimensions.

This footage shows Kaecilius wielding two Scythe daggers, as he did in the prequel comic, but no further details were given for this character, including whether or not he is actually a mystic arts master. Hopefully this preview is just the first of many, since there is very little we know about other cast members such as Rachel McAdams, who is reportedly playing the Night Nurse, Michael Stuhlbarg, Amy Landecker and Scott Adkins.

Scott Derrickson is directing Doctor Strange from a script he co-wrote with longtime collaborator C. Robert Cargill, who he co-wrote Sinister and Sinister 2 with. This superhero adventure hits theaters on November 4, going up against Lionsgate's Hacksaw Ridge starring Mel Gibson and DreamWorks Animation's Trolls, featuring the voices of Anna Kendrick and Justin Timberlake. Take a look at this new preview and stay tuned for more on Doctor Strange.