Will topline the long-gesting adaptation…

Charlie Hunnam (‘Pacific Rim,’ ‘Sons of Anarchy’) has been tapped to replace Benedict Cumberbatch in the lead role in James Gray’s ‘The Lost City of Z,’ says THR.

Hunnam will star opposite Robert Pattinson and Sienna Miller for the story of English soldier-turned-explorer Lt. Colonel Percival Harrison Fawcett, who disappeared, along with his party, in 1925 while searching for the mysterious Lost City of Z.

Long-in-development, the project is based off the bestselling non-fiction book of the same name by David Grann.

Producers on the adaptation include Brad Pitt and his Plan B Entertainment partners Dede Gardner and Jeremy Kleiner, and Dale Johnson and Anthony Katagas.

Gray is expected to get cameras rolling on the long-gesting project this summer.