A famous swedish author named Jan Gilliou has made a series of book about a man named Arn (there's 4 books in total called "Road to Jerusalem" "The Knight Templar" "The kingdom at the end of the road" and the last book "The heirtage after Arn").

To sum it up, in punishment of bedding his loved one at young age Arn gets sent away to serve in the Knight Templar order for 20 years in the holy country while his loved one Cecilia is locked into a convent in sweden for same time period. The book "The knight templar" is about this period of service during these 20 years and I guess that the movie will be about that aswell.

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