In that case then, I reckon the previews told you just the right amount of information you needed to let you avoid this, since Alien first contact isn't what this movie is remotely about.
It's like complaining that the trailers for Star Wars reveal it's set in space, rather than the documentary about celebrity feuds that you really wanted instead.
Or seeing Titanic because you see old Rose in the previews, pretty obvious in a tragic tale that she'd lose the love of her life when the ship sank. How the story is told, and the work of the actors doing it is every bit as important as the plot itself.
I'm not so sure about the Titanic example, the film's quite clever in that it tells us Rose's name was once Dawson, sure we might join the dots and figure out she and Jack don't have decades of marriage together, but early on in the film it's perfectly plausible that both Rose and Jack survive, get married and then, who knows, maybe Jack leaves her in 1925 or he dies in 1929, or she leaves him in 1930. It's definitely a feint to give us hope that Jack survives as well.
No, it's pretty telegraphed, in just knowing how movies -and tragedies themselves- work that Jack's survival wasn't likely. Hell, he was a third-class male passenger that alone doesn't put the odds in his favor. That said, when watching the movie I was truly upset Jack died and wanted to see him and Rose live happily ever after. It's possible I was a teenage girl in 1997.
Regardless, knowing the general arc or premise of a story shouldn't negate enjoying it unless there's some aspect of it that'd negate needing to see it. I'm going to use "The Sixth Sense" as an example. Right up until the last few minutes of the movie it's a pretty mediocre, tame, movie that's nothing spectacular. But then the surprise ending come in those final few moments that pretty much blows the lid off the entire thing, making it all worth it. Certainly a case where spoiling the movie would ruin it as the movie is more about the ending than the journey. (Or at least the point in watching the movie.)
With "The Martian" it's clear the point of the movie isn't the survival of Damon's character as it's pretty much a given just given the type of movie it is. (Likening it to Apollo 13 is probably a good idea) The point of the movie is the journey he and the rest of the characters take through the entire ordeal. So knowing that "The Martian" is a stranded, human, astronaut who likely survives his ordeal shouldn't ruin the movie. The movie isn't about the fate of the characters' lives but the journey they take through it all. I mean in "Lord of the Rings" the entire premise is destroying the three rings, something that's pretty much a given they'll succeed in given the adventure movie tropes and that it'd be a waste of everyone's time to spend so much time on a doomed mission.
But the point of the movie isn't whether they succeed in their quest but it's what happens through it all, the trials they face and the impact it has on them.
Last edited: