El Tigre/Juan Darien

"Based on the old folk story of 'Juan Darien' by Horacio Quiroja [i.e. Quiroga], relating the morlaistic [i.e. moralistic?] value of 'a life for a life' and the transformation it makes in the life of the avenger, the animal becomes a human and then reverts back to an animal by an act of revenge"--Page 4 of cover.