Sherlock Holmes director Guy Ritchie's King Arthur movie is currently being (unofficially) referred to as both King Arthur: Knights of the Round Table and Knights of the Round Table: King Arthur, as well as simply King Arthur. It seems likely that the film will, in fact, have a subtitle since it's meant to kickoff a six-part saga about the eponymous character, but for the time being Warner Bros. hasn't announced the official name for the historical action/adventure.
The studio has, however, started to assemble a cast for the movie, and for a while the roster was poised to include Idris Elba playing a Merlin-esque mentor to King Arthur (as played by Elba's Pacific Rim costar, Charlie Hunnam). However, a deal with Elba failed to materialize, and now the role that the Luther star was circling is being eyed by Oscar-nominee Djimon Hounsou instead.
Hounsou, who Variety reports is currently in talks to play the as-yet unnamed figure "who trains and mentors" Hunnam's Arthur in Ritchie's feature, appeared in Guardians of the Galaxy earlier this year and lent his voice to How to Train Your Dragon 2; he'll be appearing in Seventh Son and Furious 7 in 2015, followed by his role in director David Yates' Tarzan in Summer 2016 (with King Arthur currently set to arrive just a couple weeks after Yates' film). In short, he's a talented actor (and a hardworking one) who's clearly gotten comfortable playing a variety of roles in big franchise titles of late.
Will Hounsou's Arthur film role span more than a single installment (assuming the box office warrants additional installments)? It's certainly possible but seeing as story details on this new screen rendition of the Arthurian legend are under-wraps for now, it remains to be seen how significant (or not) a part the Merlin-y character will play in Ritchie's movie.
King Arthur was penned by Joby Harold - executive producer on Edge of Tomorrow (and an uncredited screenwriter) - and the cast so far looks to include Astrid Bergès-Frisbey (Pirates of the Caribbean: On Stranger Tides) as Guinevere and Jude Law (Dr. Watson in Ritchie's Sherlock Holmes films) as an as-yet unidentified villain. We've still got a fair amount of time for additional casting updates, ahead of production on the project getting underway sometime in the first half of 2015.
Ritchie delivered a fresh rendition of the Sherlock Holmes universe that resonated with filmgoers in the 21st century, and Warner Bros. is clearly banking on him managing a similar trick with the studio's The Man from U.N.C.L.E. movie in 2015 and then again with King Arthur in 2016. The director's putting a solid cast in place, but it remains to be seen what stylistic approach he goes with on the Arthur story (and how it compares to his previous work).
King Arthur (or whatever it ends up being titled) opens in U.S. theaters on July 22nd, 2016.