T2.
Predator is amazing, but T2 set a new benchmark for action movies and realised the original movies core concepts in a way that both enhanced and subverted the original in meaningful ways, all with a phenomenal cast that managed a range and delivery of performance in one movie that some actors and actresses fail to achieve in their whole careers.
Arnie in particular deserves massive praise for his depiction of the slowly learning and ever more human T800, beginning the movie right where he left of in The Terminator as the same methodical and emotionless killing machine, the slow changes in behaviour as the story progresses, clearly adopting mannerism based on Ed Furlong's interpretation of young John Connor, then eventually becoming his own unique personality, is quite honestly an amazing acting turn given that there is a clear progression of these traits through the film, despite the complexity of the shooting order compared to the final edit, that marks what is arguably the high point in his acting career.
The same too can be said of Linda Hamilton, who's Sarah Conner is so often compared to Sigourney Weavers Ripley for good reason, who takes the character to the ultimate conclusion of the first film, becoming as much the emotionless killer as the machines she is a victim of, only to be saved by the maternal bond she shares with and core of humanity exuded by John Conner, in a mirror of the T800.
Plus it's just a brilliant movie full stop. A great dark Sci Fi horror in its own right, with a clear and meaningful message and bleeding edge special effects pared perfectly with the height of practical ones. It is as close to perfect as any film can be expected to be.
