Sync is a very complicated and thought provoking story about the danger of letting technology get too advanced. The idea that a computer program/virus has become smarter than it's makers and is causing havoc may be unsettling.
The main character has the ability to switch between "shells",or copies of his body. Sometimes he switches bodies after being killed. When shells are not in use, their eyes roll back into their head. At one point, the in-synced shells come alive on their own and have a very eerie appearance.
A character has a badly scarred face due to an acid burn.
A character is suddenly approached, shot, and dragged into a van. This all happens right in front of his fiance's eyes, who is shocked and begins crying hysterically.