Entertaining? Sure, but frustrating and mind boggling dumb is more like it.
Think of the historic Knight Templars and then forget everything about them because the show does its best to skew them. The Hollywood spin off replaces the vows of chastity and service to God with sex and bloodlust. The "heroic" protagonist and Templar leader in the show is everything Templars forbade and treats the order like a mercenary group rather than a monk order. God is practically non existent in the show save for a few catchy phrases and well timed genuflects, and no one seems the least bit focused on religion at all. It's just another twisted love story with angry Kings and tough knights. Best I can say about the show is at least the fight scenes are cool.