1. A Clockwork Orange (1971)
The film which spawned the term 'ultra violence' and which definitely lives up to that title. Alex is a roguish juvenile delinquent who runs about with his mates - the droogs - creating havoc wherever they go. At the beginning of the film Alex and his pals go on an orgy of violence after drinking 'milk-plus'. First they beat up an old tramp for no reason and then they have a fight with a rival gang. But this all pales into insignificance when they steal a car and drive to the countryside. They stage a home invasion of the writer F Alexander's house and beat him up until he is crippled. They then rape his wife while singing Singin' in the Rain. The most disturbing aspect of this attack is the amount of sadistic glee Alex gets from it. He is positively revelling in the rape of a woman and singing while he degrades a woman is not only an act of ultra violence but also an act of complete and utter debasement.