Marvel Studios' "Doctor Strange" pits world-famous neurosurgeon Dr. Stephen Strange against the villainous duo of Kaecilius and the dreaded Dormammu -- but if the original plans for the film had come through, Strange would have faced a different foe.

In an interview with Empire, director Scott Derrickson reveals that instead of facing two mystical threats, Strange was originally set to battle the ruler of the Dream Dimension, Nightmare.

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Marvel Studios President Kevin Feige made the final decision to forego using Nightmare, citing complications with introducing the villain's home reality. "The trouble with starting with Nightmare is getting across the idea of the Dream Dimension as another dimension," Derrickson explained. "The movie was challenging enough. It's already an exposition-heavy movie... Dormammu made the most sense. And he is the most present villain in the comics."

Debuting at the same time as Doctor Strange in 1963’s “Strange Tales” #110, Nightmare is the sinister ruler of his own world within the Dream Dimension who influences, and torments, the dreams of humans as they sleep. Frequently depicted astride his demonic horse Dreamstalker, Nightmare has been a frequent foe of Stephen Strange, and has faced Ghost Rider, the Incredible Hulk and Spider-Man, among other Marvel superheroes. Nightmare and Doctor Strange are featured prominently in the new direct-to-DVD animated film “Hulk: Where Monsters Dwell."

If fans are disappointed in not seeing the Dream Dimension brought to life on the big screen, there is still hope. Derrickson is a big fan of the Nightmare character and believes he could make an appearance in a sequel.

“Doctor Strange” is currently in theaters, and stars Benedict Cumberbatch, Chiwetel Ejiofor, Rachel McAdams, Benedict Wong, Michael Stuhlbarg, Benjamin Bratt, Scott Adkins, Mads Mikkelsen and Tilda Swinton.