The following contains spoilers :
1. Many flaws in the movie: like the people walking around who didn't know they were pricked in the neck three times.
Also, the physicist who created the neck prick weapon to eradicate bad people was the same physicist who obtained the technology from the future inspired from himself. That's circular creation. Crazy!
So, why didn't the assassin just introduce herself to her grandfather during their first encounter in 1988? But then, you wouldn't of had a movie. Lol
lastly, grandad forgets to mention to his grand-daughter that before her mission when she goes back in time, he will be trying to kill her every nine years that she shows up in his world, inevitably killing her.
He should have sent her back to try and save his wife! But I guess that wasn't important.