Based on Kurosawa's Rashomon, this is all about the uncertainty of knowledge. A rape and a murder occur in the forest but four witnesses, including the raped woman and the murdered man, give inconsistent descriptions of what happened. Are they lying in their own self interest, or do they believe what they say? Was the woman actually raped? Did the man perhaps commit suicide? What happened? We don't know.
Provost's movie adds to this. He takes the Kurosawa film, splits and reflects it and transforms it into a pulsing butterfly that is infused with flashes of anguish and horror from the original film. What is it that we're looking at? We are not sure. What just happened? We don't know.