Not to be outdone by Robert Downey Jr.'s Illumnati set photo yesterday, the Russo Brothers shared a new image from Avengers: Infinity War today, which returns to the Sanctum Sanctorum from Doctor Strange. While the good Doctor himself (Benedict Cumberbatch) wasn't present, this image does feature Doctor Strange director Scott Derrickson, who shared the image on Twitter. Unfortunately, neither the Russos nor Scott Derrickson would shed any light on what is being shot in the Sanctum Sanctorum as of yet.

The image debuted on both the Russo Brothers Instagram and Scott Derrickson's Twitter early this morning, which shows all three filmmakers looking over what is likely the script for Avengers: Infinity War, presumably for a scene involving the Sanctum Sanctorum. Benedict Cumberbatch just began shooting on Avengers: Infinity War last week, nearly six months after filming got under way. We reported in January that a stand-in would be used for Benedict Cumberbatch, as he finishes shooting the true story adaptation The Current War, where he portrays Thomas Edison. Broadway actor Aaron Lazar was brought on to serve as the actor's stand-in, with Benedict Cumberbatch said to reshoot all of the scenes where his stand-in's face was shown.

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The Sanctum Sanctorum was first established in last year's Doctor Strange, which also featured a post-credits scene in the New York Sanctum, featuring Chris Hemsworth's Thor, which will tie into this fall's Thor: Ragnarok. As for Avengers: Infinity War, since there is practically nothing confirmed about the story thus far, it's anybody's guess why the Sanctum is being used, but we did see both Doctor Strange stars Benedict Cumberbatch and Benedict Wong having lunch together in yesterday's set photo, and it's certainly no coincidence that this set photo comes just a day after both Doctor Strange stars were spotted on the set.

It's possible that the Sanctum scenes will have something to do with the fifth Infinity Stone, the Time Stone, which was part of the Eye of Agamotto. After the events of Doctor Strange, the Time Stone was placed back in the library of the Kamar-Taj in Tibet, with Stephen Strange promising to never wear it again in public until he learns how to master its powers. While the Sanctum Sanctorum doesn't connect to the Kamar-Taj, it's possible that some of Thanos' forces may believe the Time Stone is there, which could be why there are scenes in the Sanctum Sanctorum, but that is pure speculation at this point. Still, with Strange and Wong coming back for this adventure, there could be any number of reasons why the Sanctum Sanctorum, or possibly the other Sanctums in London and Hong Kong are being used.

While at first Marvel was planning on shooting Infinity War and Avengers 4 at the same time, the studio decided to shoot both movies separately. After Avengers: Infinity War wraps production, the cast and filmmakers will have a short break before starting production on Avengers 4. The title for the fourth Avengers movie is said to be a spoiler for Infinity War, so we likely won't know the Avengers 4 title until after Avengers: Infinity War hits theaters on May 4, 2018. Until then, take at the latest photo from the Avengers: Infinity War set.