Filmmaker Scott Derrickson left Doctor Strange in the Multiverse of Madness after working on it for several months citing a conflict of interest with Marvel Studios over the direction the project was taking. Now, while talking to fans on Twitter, Derrickson may have unconsciously dropped a valuable hint about the terrifying inspiration behind the Doctor Strange sequel.

Let's start with the necessary context. Recently, fans asked Derrickson if he would be interested in making a Star Wars movie. The filmmaker has made his name in the horror genre, directing such cult classics as Sinister and The Exorcism of Emily Rose. As such, it was no surprise when Derrickson wrote that he would like to make a horror-movie about the ice planet Hoth with all-new characters, inspired by stories like The Thing and In the Mountains of Madness.

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Here's the thing. In the Mountains of Madness is a story written by celebrated horror icon H.P. Lovecraft, and deals with an arctic expedition where the explorers discover ancient alien monsters lurking in the snow. But the story is actually titled At the mountains of Madness, not 'in'.

You know what movie title does have an 'in'? Doctor Strange in the Multiverse of Madness. The Doctor Strange sequel that Scott Derrickson was working on before he had to leave the project. Could it be Derrickson had Doctor Strange in mind when he mentioned The Mountains of Madness in his tweet? And does that mean that the Doctor Strange sequel has been inspired by the Lovecraft classic?

This would bear out with what Derrickson had said in the past when he was still attached to the project, about Doctor Strange being Marvel's first horror movie. In place of Doctor Strange going to the arctic, he would enter into the multiverse instead, and encounter horrors, unlike anything he had seen before.

To lend further credence to the theory, Derrickson deleted the tweet soon after posting it, which seems like a strange thing to do with an innocent tweet about a hypothetical Star Wars movie, unless Derrickson realized his little slip could give fans spoiler information about another important project he had already worked on.

Whatever the truth of the matter, whatever Scott Derrickson had planned for Doctor Strange, it is clear that his ideas were too radical for Marvel. When Kevin Feige was asked about Derrickson's comments about the Doctor Strange sequel being a full-on horror, he was quick to clarify that the movie was going to be a regular action-adventure with horror elements. Which means we will most likely be getting a watered-down version of the vision Derrickson had for the film.

Whether or not Doctor Strange in the Multiverse of Madness will manage to scare the pants off you, it will be great importance for the future of the MCU, since it will open up the cinematic universe to multiple other realities from which all manner of heroes and villains will emerge to make the cast of the franchise even bigger and more explosive first brought forth this story.