A Season One episode contains a man being hypnotized, whist a doctor cuts through his skin, this can be a little freaky but no blood/gore is shown
Throughout season 1, there is lots of violence and some accompanying bloody images. People are executed by being shot in the head, a man is stabbed in the throat, people explode (no gore), a guy gets hit by a car, there are fatal shootouts, a theater full of massacred dead people is shown with blood all over, a little girls neck is broken, etc.
Violence is less frequent in season 2.
Several people shot in the head (execution style)
A man is stabbed in the hand before being shot in the head.
A short scene of torture can be seen near the end of season 1. People begging for mercy before being killed.