(At the time of writing I've seen five films directed by the Québéquois Denis Villeneuve, and although they are all different from each other they all involve similar plot elements: an incident triggering existential crisis, and a change of psychic state at or towards the end. For this reason I include this paragraph in parenthesis in each of my comments on the five films.)
Incendies has a highly complex plot, which I'm not even going to begin to explain: suffice to say that a lawyer, whose former secretary has just died, reveals the contents of the mother's will and gives a letter each to the son and daughter: one to be given to the mother's husband, and the other to their brother. The problem is that neither son nor daughter knew that they had a living father, or that they had another brother at all. This is an at times violent film in which we see the quest of a mother for a son, and then the quest of a daughter (later a son too) for a brother. It's also a story of torture and rape, of unknown incest, where a torturer becomes a father to twins: the son and the daughter. By far the best Denis Villeneuve film I've seen.