2.Terminator 2: Judgement Day (1991)
T2 is easily one of the greatest sequels in any franchise. It had great action sequences and the director pushed the limits of the film's special effects. Combine all that with a great story makes T2 still, a referencing point on how a sequel can build off the narrative of its predecessor. I even say, T2 has a better story, character arc & FX than the original. The only is issue was that Arnold Schwarzenegger still looked more bad ass the villain. And that has been an issue with the franchise ever since. The villains may have superior powers but they all lacked that presence that Arnie had in the films.
While T2 is an amazing sequel and pushed the boundaries of FX, it still lacked the presence of a truly terrifying Terminator, hunting down our heroes.