The Templar trials of 1307-1314 are well documented by their records which were investigated by many scientists. There are, for instance, Malcolm Barber's classic The Trial of the Templars (2006), Helen Nicholson's The Proceedings Against the Templars in the Britisch Isles (2011), and more recently Alain Demurger's The Persecution of the Knights Templar: Scandal, Torture, Trial (2015/2020).
However accurate and descriptive these monumental scientific studies are, they focus mainly on the scientific facts, as they should. They are not intended to elaborate on how the people of the day, the Templars concerned in the first place, experienced, felt about and dealt with what happened. For this, historical fiction may come to the rescue, as far as it is sufficiently researched and based on historical data. A good example of such a novel is Non Nobis by Hanny Alders.