For the longest time, Robert Downey Jr. headlined the most lucrative action franchise of all time in the shape of the MCU. Other film studios have also attempted to cash in on that "shared universe" sensibility with their own franchises, to varying degrees of success. Now Downey has declared his intention to start a new shared universe, this time dedicated to the world of Sherlock Holmes. The actor spoke to Fast Company about his desire to add some diversity to the world of the master detective.

"At this point, we really feel that there is not a mystery-verse built out anywhere, and Conan Doyle is the definitive voice in that arena, I think, to this day. So to me, why do [Sherlock Holmes 3] if you're not going to be able to spin off into some real gems of diversity and other times and elements?"
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Speaking about their desire to create a shared "mystery-verse" via their production company, Downey Jr.'s wife, producer Susan Downey explained how the world of detective fiction was ripe ground for franchise expansion.

"We think there's an opportunity to build it out more. Spin-off characters from a third movie, to see what's going on in the television landscape, to see what Warner Media is starting to build out, things with HBO and HBO Max."

Robert Downey Jr. took on the role of Sherlock Holmes in 2009 in the Guy Ritchie-directed movie Sherlock Holmes, which his wife produced. Most recently, the duo used their experience in the genre to create a gritty reboot of Perry Mason that has already been renewed for a second season.

While franchises are nothing new in Hollywood, a shared cinematic universe comes with its own set of rules and expectations. No other such entity has had the kind of success as the MCU, and Susan Downey was quick to credit the Marvel creatives for showing them how it's done.

"I do think that the decade of tutelage and observation, what we were both able to have with Marvel, watching them build out and see all the opportunities, was invaluable. It was like a master class. And they really did know what they were doing and they had this tight-knit group of people from [the] jump locked into a vision that enables them to broaden" the comics into 23 hit movies (so far)."

Although The Incredible Hulk was the first entry in the MCU, 2008's Iron Man starring Downey Jr. is generally understood to have been the blueprint for success that all other movies that followed in the series have since been trying to emulate. For the actor, getting to view the work being done up close allowed him to understand the various factors that go into determining the success of a shared cinematic universe.

"What I saw was very humble beginnings, very uncertain outcomes, a lot of creative risk-taking, but there was also an algorithm to the potential. It's also having the right people. Different sensibilities will get you to different places downfield."

This news comes from Fast Company.