The Fly (1986)
David Cronenberg directs this meditation on obsession and power, creating a pitch perfect mad scientist story.
When an experiment goes horrifically wrong, scientist Seth Brundle begins to experience a metamorphosis that threatens to overtake his humanity. Cronenberg handles Brundle's transformation into a giant fly masterfully, utilizing creature effects that still make audiences sick to their stomachs thirty years later. Truly one of the better examples of the modern monster movie, and perhaps the greatest horror remake of all time.