My thoughts on why, and what I'd have done differently if I was writing it, below.
Are you clear? Big spoilers.
In other words, if you're planning on seeing it and you don't want to know what happens, bookmark this and come back to it.
Also, I should point out numerous people have done alternate versions of Passengers on Twitter and they're all really good - I particularly like this one by Elizabeth May.
Okay, so, Passengers.
From the trailer, I thought I knew what to expect. Chris Pratt (Jim) and Jennifer Lawrence (Aurora) wake up together in space, 90 years before they should come round, and still far far away from the planet they're heading towards. Cute romance ensues, until some sort of disaster happens.
I avoided spoilers on Twitter prior to seeing it but there were clearly a LOT of people unhappy with what they'd seen/read about, so I figured it didn't happen quite like that.
What ACTUALLY happens is that Jim wakes up, is by himself (except for android bartender Arthur, played by Michael Sheen) for a year or so, and eventually decides to relieve himself of the boredom by waking Aurora, who he's become obsessed with. (This is despite Arthur's response when Jim explains that if he does this he'll be stranding her with him for the rest of her life, which is a rather sensible quote along the lines of "Well, you can't do that then." LISTEN TO THE ANDROID JIM!)
Romance ensues (obviously due to Jim not TELLING Aurora he's done something frankly completely unforgivable) until she finds out via Arthur what he did. Unsurprisingly she is furious at this violation, tries to avoid him, he tries to pressure her into forgiving him - including using the ship's intercom to talk to her wherever she is. Then Laurence Fishburne's character (Chief Deck Officer Gus) wakes up. Although he dies fairly quickly due to health problems caused by his malfunctioning hibernation pod, he's able to see that something is wrong with the ship - causing both him and Jim to wake up - and will cause more problems unless it's fixed. Using his crew ID to gain access to things they couldn't access before, they're able to repair the ship, with Aurora having to rescue and resuscitate Jim after he's trapped outside.
At this point, things REALLY break down for me. Jim finds that with Gus's ID he can put Aurora back into hibernation in the medical pod (Robodoc? I can't remember the exact name) but as there's only one medical pod, he will be left living alone, although she can then have the life on Homestead II she planned on having.
She chooses instead to stay with him, and the film ends with the other passengers waking up 90 years later to see the ship filled with wildlife that Jim and Aurora had nurtured, as a voiceover tells us that they found happiness together.
Yes, she found happiness with the guy who stole her entire life from her.
It's clear that Passengers is meant to raise questions - "Is what Jim does understandable?" "Should Aurora forgive him?" and, of course "If you were in his place would you do the same thing?"
The biggest question of all it raises, though, is "How many people in Hollywood had to give the go-ahead to that ending, and didn't ANY of them think there might be a better one?"
I think stories exploring Stockholm Syndrome can be powerful. I think unlikeable and flawed protagonists can be great characters. But to have someone do something THIS awful and then end up with a romantic happy ending?
Just dire. Completely and utterly dire.
And the frustrating thing about it, for me, is that at times it DID seem like it knew Jim's behaviour was super-creepy, and that it was acknowledging it. But the ending completely negates all of that.
So here's an alternate one.
Everything happens as it does in the film until the bit where Jim tells Aurora she can go into hibernation in the autodoc.
She says that she wants time to think about it but that she might want to do it so they should enjoy the time together.
Montage of dancing/basketball/etc cut with her going to the plants, writing, etc.
Eventually she says it's time, they hug, he puts her under, goes to the bar.
Arthur asks Jim if she's gone back into hibernation and, when he says yes, hands him his usual whiskey. Jim drinks it, collapses in pain. Arthur tells him he has a message from Aurora.
V/O "I know you put me back to sleep, and did the right thing in the end. But how could I sleep knowing that you could do the same thing to another innocent girl next time you felt lonely? You just drank a poison which is going to make the rest of your life VERY short and painful."
Jim dies alone.
90 years later, Aurora is woken up, gives a glossed-over account of what happens, becomes a celebrity on Homestead 2. As planned, stays there a year, then returns to Earth, where she lives a long and successful life as a writer with a unique story to tell. Just before she dies of old age, she publishes what will be known as her most famous story - the truth behind Passengers.