The various models of the Terminator:
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The movies in the Terminator series have been on a long slide downhill and T-4, excuse me "Terminator Salvation" accelerates the descent. The first movie was a pretty good story. After that, each movie chipped away at having a coherent story, though T-2 was good with Linda Hamilton transitioning from terrified waitress in T-1 to guerrilla master in T-2.
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T-3 had long extended action sequences that were reminiscent of a Warner Brothers cartoon, including an extremely ridiculous chase sequence in which the bad terminator, driving a large crane, chased the good terminator and John Connor. T-4 substitutes the long chase scenes of T-3 with a lot of loud explosions and sets that make the movie Sin City look real by comparison. Like every movie in the series since T-2, this one has a "good" terminator, though this one, for reasons best left unexplained (if you still want to see this steaming pile of dreck), comes to fight on the side of humanity on its own.
Script pitch: Year 2018. Good terminator helps John Connor save the young man who will become his father. The two blow up Skynet's base in San Francisco. Good terminator sacrifices himself to save Connor. Fade to credits.The Terminator series needs to end, now. The next person to pitch a T-5 concept should be flogged with barbed wire.
Collect up all of the Terminator models and melt them down.
(We'll be dealing with the real thing by the end of this century, anyway.)