Theory: Why didnt donnie know Frank was his sisters boyfriend?
Growing up with siblings, we usually know who our siblings are dating, esp if they go to the same school. So why didnt Donnie know Frank when Frank took off his mask in the theater?
It could be assumed he didnt know him, or frank wasnt in high school. But thats a bit boring, considering Donnie's psychiatric problems, I think he blocked out franks identity. He knew him, but because of the timeline shift, he blocked it out. SO when Frank revealed himself, Donnie acted like he didnt know him.
I just always found it hard to believe that Donnie didnt know Frank. I mean my brother is 7 years older then me, and I still knew his girl friend. If she was in a bunny suit, I would of recognized her when she took off her mask. SO Why didnt Donnie know frank?
He blocked him out mentally. We could see he was susceptible to hypnotism, so maybe even Frank, was blocking Donnie from realizing who he was. Either way, this is one of the last unanswered questions of the film.
Does anyone know if the director/writer ever touched on the subject?