Although thousands of characters still sit, unused, within the Marvel library, fans have long wondered if, or when, the studio might bring one of its oldest superheroes to the big screen: Namor, the Sub-Mariner. Studio President Kevin Feige has long expressed a desire to introduce the prince of Atlantis into the Marvel Cinematic Universe, while acknowledging an entanglement of rights complicates the matter. But a tweet by Doctor Strange director Scott Derrickson may indicate Namor could make his cinematic splash sooner rather than later.In the now-deleted tweet, Derrickson shared an image, from the cover of 2011's Fear Itself: The Deep #1, depicting Strange and Namore. It was accompanied by the text, "Are You Experienced?," a referenced to the 1967 song by the Jimi Hendrix Experience.

The film rights to Namor were sold in the 1990s to Universal Pictures, but have since returned to Marvel Studios and Disney. However, Feige has indicated there are contracts with "other parties," likely a string of producers who became involved with the property over the years, which complicate the handling of the Sub-Mariner.

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Doctor Strange and Wong are expected to return in Avengers 4 ahead of Doctor Strange 2. Directed by Joe and Anthony Russo, the film stars Robert Downey Jr., Chris Evans, Chris Hemsworth, Brie Larson, Mark Ruffalo, Jeremy Renner, Scarlett Johansson, Paul Bettany, Anthony Mackie, Paul Rudd, Elizabeth Olsen, Tom Holland, Benedict Cumberbatch, Chadwick Boseman, Chris Pratt, Zoe Saldana, Dave Bautista, Bradley Cooper, Vin Diesel, Karen Gillan, Evangeline Lilly, and Josh Brolin. Avengers 4 is set to hit theaters on April 26.

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