A Clockwork Orange (1971)

A Clockwork Orange (1971) remains Stanley Kubrick's most controversial work, with its ultraviolent dystopia earning an X rating in the UK that restricted viewings for 27 years. The film's use of Beethoven's Ninth Symphony as a tool for conditioned aversion training cost $2.2 million to produce, earning $26 million worldwide. Its banned status in Britain until 2000 cemented its reputation as a dangerous masterpiece, a label no other entry on this list can claim.