Summary from GoodReads:

Does a mysterious manuscript, discovered by chance in the library of a Burma's monastery, contain the oldest thriller story of Southeast Asia literature? In the far east of the Indochina peninsula during the Ninth Century A.D., young Prince Asaka fights against the intrigues of the Khmer Court. A son of the Khmer King is found assassinated: why would somebody want to accuse an innocent poor slave of such an important crime? Our hero, also involved in the crime, as owner of the slave as well as more directly, manages to extract himself and to identify the true culprit, thanks to the help of two friends. Twists and turns are abundant in the story; and in the final hearing, although according to the canons of Anglo-Saxon law the development of the latter is unusual, we do find the Public Prosecutor and the Defense Attorney, with abundant cross-questioning ante litteram of the testimonies, documentary proof as well as circumstantial. Not a classic thriller, but rather a mixed genre of police, adventure and spy-story.