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)