The 22-year-old actress struggled to keep her composure for a question and answer session after the film's ongoing Toronto International Film Festival (TIFF) debut.
"This is, like, the third time I've seen the movie and it still makes me cry. I had to run out and try and fix my face for the Q and A because I was such a wreck," she said.
Watson, Nina Dobrev, Logan Lerman and their castmates were given a standing ovation after the screening.