Just announced by King himself on Twitter:
https://twitter.com/StephenKing/status/704674793145159680
EDIT:
Idris Elba & Matthew McConaughey on Twitter:
https://twitter.com/McConaughey/status/704679948179484672
Entertaiment Weekly article with more details:
http://www.ew.com/article/2016/02/29/dark-tower-rises-stephen-king-idris-elba-and-matthew-mcconaughey
https://twitter.com/StephenKing/status/704674793145159680
EDIT:
Idris Elba & Matthew McConaughey on Twitter:
https://twitter.com/McConaughey/status/704679948179484672
Entertaiment Weekly article with more details:
http://www.ew.com/article/2016/02/29/dark-tower-rises-stephen-king-idris-elba-and-matthew-mcconaughey
It’s easy to imagine that phrase being The Dark Tower’s version of “A long time ago, in a galaxy far, far away …,” serving to introduce almost any part of the saga. But this first film will not adapt the plot of the first book, The Gunslinger, published in 1982.
“[The movie] starts in media res, in the middle of the story instead of at the beginning, which may upset some of the fans a little bit, but they’ll get behind it, because it is the story,” King says.