OK, so it's not often an anime this dark comes around, and so I just had to check it out. I haven't read the manga (if there is one), so I'm not sure if this follows closely or not. And without dropping any spoilers, it would appear a second season may be coming. Hopefully it will wrap things up.
Tokyo has two types of inhabitants, humans and ghouls. Ghouls look like humans, but can transform into monsters, have special blood-type weapons and other powers and have to feed on human flesh. All other food is repulsive to them. One day, Kaneki, a normal high school boy, has an accident and is given an organ transplant from a ghoul and becomes a half-human, half-ghoul hybrid. He learns that not all ghouls are horrible, man-eating monsters and some just want to live normal lives. He also learns that isn't easy for his kind.
This show had great character depth and animation and was pretty hectic with the violence and despair. But it was also censored to pieces and the ending was vague. The second season may clarify some things. Watch it...without your kids haha.