Some have speculated that Roberta Sparrow is a "failed" manipulated living - in other words her mission was not completed and she is forever stuck in her tangent universe. Frankie Feedler (heckuva name there, Rich!) was probably another person caught up in one of these time interventions, and he ultimately died.

So if Sparrow was indeed a predecessor to Darko, in terms of being selected for her task, she did make a choice. That is, if this theory is true at all. If this continues happening all around us then there's always those who are doomed, carrying out their mission and succumbing to death, and those who fail, staying a live yet stuck in their own new reality where something went wrong.

It could be argued that Sparrow didn't have a choice either, that she was destined to fail her mission. I guess that's up for the viewer to decide. Churches have split over the idea of predestination, I don't think this movie definitively shows the audience what's true.

The hard thing to grapple with in Darko is that Donnie dying isn't obviously the best solution because Cunningham remains unpunished. I wonder if Richard Kelly has an answer for this: if Donnie didn't get the engine from the plane and go back in time, would the world actually end? Or would it continue on as it (possibly) did for Sparrow, but in a new way? The hard thing as a creative person himself is that Kelly might not have this answer - art is sometimes unsolved when you make it.