The structure of the Terminator is pretty damn perfect. The first 30 mins we frankly have no idea what's really happening. Two naked guys show up, both lookin for Sarah Connor. We see glimpses of a future war but we don't grasp the connection between that and the present. It's only at Tech Noir, half a hour of intrigue later, all three major characters combine, and one of them tells our targeted protagonist, "Come with me if you want to live!". Then the next hour or so is just pure cat and mouse thriller, with tense bursts of exposition in between chase scenes and shootouts.
Linda Hamilton is frankly extraordinary in this movie. She has to very quickly sell us on being a likable confused nobody, to a terrified but more confused prey, to vulnerable but coming to terms with the situation, and finally a battle hardened survivor who refuses to give up. All the emotional attachment comes through the consistent characterization of her performance, in the rare moments of downtime the narrative affords her, and she just kills it. She's the beating heart inside the machine of a movie.
And what a machine it is! The work of a filmmaker who grew up in the trenches under Roger Corman and had something to prove. Cameron knows how to stretch his limited budget for maximum value, with a full commitment and confidence that this movie was gonna be major. You can tell with more time and money, this guy was gonna make the biggest movies in the world. Yet I'm not sure he's ever made a better one.
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...that said, T2 definitely gives it a run for its money.
If the original Terminator was the raw exciting self titled debut album, then Terminator 2 is the big studio backed sequel. It plays a lot of the same notes, but considerably more polish and shaped towards mainstream taste. The pulpy horror/noir b movie genre flourishes have been exorcised in favor of bombast and humor. It's a much warmer movie, with the once fearsome T-101 given a heartwarming arc from stone cold killer to surrogate father figure.
T2 also flips the cynical philosophy of T1 on its head. The original story proposed that our free will is an illusion and everything that's gonna happen, will happen. Adult John Connor sends Kyle Reese back in time because he's secretly the father. Kyle protects Sarah and leads her from aimless scared twenty something to battle hardened (pregnant) warrior. She's get her picture taken on the way south to Mexico because she always was gonna have it taken, cuz that exact pic was gonna end up in Kyles hands 40 years later. It's a closed circuit with no room for deviation. T1 says Judgment Day is inevitable and billions are gonna die, but at least we can fight back.
T2 says this is bullshit. The actions we're taking now matter, and the future is fluid. There's no fate but what we make. Instead of being a reactive story of humans trying to survive an apocalyptic future, it's an active story about a group of people taking destiny back by their own hands.
The greatest invention of T2 helps sell this optimism. I'm talking, of course, about Sarah Connor. Continuing her arc from the ending of T1, she now a full blown warrior woman, with a tight wiry physique and the worlds most intense eyes. She's burnt off any of the soft human sides of herself she saw as weakness, almost as if she's fighting fire with fire with the unstoppable uncaring Terminators. Linda Hamilton is frankly amazing as a driven woman who hides a fear of the future behind pure anger. The heart of this story is a return to hope, not just for humanity in general, but Sarah learning to let her own humanity back into her life. My favorite James Cameron scene ever is her sad realization that she almost became the thing she hated the most by terminating Miles Dyson, and the love she rediscovers for her son John.
These thematic and character developments make Terminator 2 seem more than a big budget rehash, but a necessary sequel and perhaps even a corrective. It's a thrilling, deeply human story, told by a director at the height of his powers. It's the best popcorn movie the 90s produced, with only a handful of films in its style having matched it since(only Fury Road has surpassed in my mind since 1991) Not sure it's better than the original, but I don't want to imagine a world where it doesn't exist.
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Personally, I voted Terminator 1 here. I'm drawn into its lean thriller machine form, its nihilistic atmosphere, its powerful character arc of Sarah Connor. But usually I'd vote for whichever one I've seen last. They're both excellent films.