Charlie Hunnam will star opposite Robert Pattinson and Sienna Miller in The Lost City of Z, Plan B’s adaptation of the book by David Grann. Hunnam is replacing Benedict Cumberbatch, who was previously set to star but is now due to topline Marvel’s Doctor Strange movie, among other projects. In the true-life drama, Hunnam will portray British explorer Col. Percival Fawcett, who disappeared in 1925 while searching for a mysterious city in the Amazon. Brad Pitt, Dede Gardner and Jeremy Kleiner are producing via Plan B Entertainment along with Dale Johnson and Anthony Katagas. Marc Butan is executive producing, as are MICA Entertainment’s Julie B. May and Glenn Murray.