Engelsfors is a Swedish young adult fantasy trilogy written by Mats Strandberg and Sara Bergmark Elfgren. All three novels in the series have been translated into English. A Swedish film adaptation of the first book in the series, Cirkeln (English: The Circle), was released on February 18, 2015. There are plans to film adaptions of the second and third books if the first film is a commercial success. Source: Wikipedia (en)