She wasn't there to collect the trade(since it took her) so the troll took it back. It was pointing out the folly in trying to make a deal with a troll.
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Nope. That is clearly not the case. What we were seeing at the end was the cop imagining a scenario where that happened. But that is NOT what happens in the movie.
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Indeed. You can't just have "It was all a dream!" at the end, that's rubbish.
I actually really enjoyed this film, and it's very interesting reading the different viewpoints on it.

lord_kobel:
Boo! That's no fun.

Another alternative to explain why they didn't find the fetus is that possibly it never happened, and all the monster stuff wasn't real in the end

The next day no one mentions the fetus. The cop would have been VERY much inclined to think that fetus was his kid, particularly when any medical examination would peg how old it was.
Yes, because Trish is the only 3rd term pregnancy in the entirety of the LA area
Why would he think the fetus is his? What exactly would lead him to that conclusion? Even if it were found, which there's nothing suggesting it was.
Instead, as was mentioned, you'd be looking at a definite murder investigation (for the fetus and possibly the mother).
You can't murder a fetus. It's only murder if the child takes a breath outside of the mother, and there's no evidence of that. It seemed pretty dead already when Calli saw it. And as far as anyone can prove, Trish is just a missing person. There's no signs of foul play.
Now, here's the thing that is really disturbing. The fetus is left as a trade. Callie is taken. The Troll knows the fetus is dead at this point, so why not take it back? For what reason?
It most likely did take it back. Why would it leave it there?
For the same reason the Troll took the dogs and cats left by Jamie Lambert.
To feed to the people trapped in the Underneath.
Most likely yes. Hence why Daniel had animal bones in his stomach. Now they're all going to have fetus bones in their stomach.
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Time clearly does not stand still. If it did we wouldn't be able to hear their screams when the troll approaches.
And where do you get these claims of folklore implying frozen time?
I don't think they'd need to eat or drink.
The movie itself proves you wrong. When Daniel came back it was explained to us that he had animal bones in his stomach. Meaning he had been fed whole animals while a captive of the troll.
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ForTheNonce:
But the folklore also says they DO eat and drink. People are warned not to eat the food in the faerie land, or whatever. And Daniel's stomach had bones and whatnot in it. Time may stand still, but also Daniel's clothes were ratty, dirty, and worn down. The point is, we don't know what is going on over there. Is time really stopped continuously? Does it slow down or speed up occasionally? If the prisoners don't
need
to eat, does that necessarily mean they
can't
eat? Or are there times they
must
eat?
I'm just saying, if we know they were eating animals because of the bones and stuff, and Jamie was leaving stray dogs and cats, and the fetus was there one minute and gone the next, and this thing is both alien and probably evil, is it a stretch to think they ate the fetus?

That's interesting.
But the problem there is there isn't enough food/water brought to them to sustain many people. If we follow the folklore, in many tales time stands still. I don't think they'd need to eat or drink.

I'm just trying to get over the fact that this is the 2nd movie I've see in as many days that showed a dead fetus. What are the odds of that? Geez

Or consider this disturbing possibility. The next day no one mentions the fetus. The cop would have been VERY much inclined to think that fetus was his kid, particularly when any medical examination would peg how old it was. Like others have mentioned, the cops wouldn't be talking about them being out there on their own. Instead, as was mentioned, you'd be looking at a definite murder investigation (for the fetus and possibly the mother).
Now, here's the thing that is really disturbing. The fetus is left as a trade. Callie is taken. The Troll knows the fetus is dead at this point, so why not take it back? For what reason?
For the same reason the Troll took the dogs and cats left by Jamie Lambert.
To feed to the people trapped in the Underneath.
I'll leave you to ponder the horror of that thought.

You can't make up events that aren't suggested, so the wild animal thing wouldn't fit.
Why not exactly? You made up rules that were never suggested. Are you the only one allowed to make things up here?
You absolutely can't say they'd just find a damn fetus and think nothing of it..especially when it's the child of one of the cops. So that is certainly ruled out.
How exactly would they know that the fetus is his? Even if they did "think something of it" what conclusion are they supposed to reach by finding a nearly full term fetus in the tunnel?
The only explanation that would fit is contrary to my initial posting, the creature did in fact take the fetus back after all.
And as has been pointed out, you had no reason to think it wouldn't take the fetus back. Since the person it was trading with can no longer collect the trade.
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Maybe Trish traded her life for the fetus, and the troll all too literally obliged. Just because it looks like the baby is for Callie doesn't mean it is.
Still, i think it is good that we NEVER get a true explanation of just WHAT went on, it is part of the point of this film. We can either believe what we see through Callie's eyes, or what we see from the detective's. Even the end could be some sort of metaphorical way of saying the detective, like Trish did with Daniel, is starting to entertain the thoughts that the troll thing as told by Callie was true. It's good how this movie offers two distinct lines of thought to interpret what happened. Did Trish imagine Daniel's ghost out of grief, or was Daniel sneaking through the cracks to momentarily see her? (Notice the apparitions happened in dreams at first, no reason to believe Daniel did that, going by what we see). Not all that terrifying, but a REALLY well put together, deeply psychological, film. It's nice to see not EVERYONE is devoid of ideas these days.

You can't make up events that aren't suggested, so the wild animal thing wouldn't fit.
You absolutely can't say they'd just find a damn fetus and think nothing of it..especially when it's the child of one of the cops. So that is certainly ruled out.
The only explanation that would fit is contrary to my initial posting, the creature did in fact take the fetus back after all.

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I agree with those who say that the fetus would most probably have been eaten by stray dogs, birds and/or wild animals. Still, there are many possibilities as to what happened to it. It may have been discovered and mistaken for some poor girl's miscarriage then taken away - remember, nobody was urgently searching for the sister because by the end of the film the only people left who were involved in the whole affair were the police, and it probably took some time before they realised both girls were now missing.

How exactly are the police supposed to know the shoe belongs to Calli and isn't just some random shoe in the street? Did she have her name written on her shoes?
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They might have found the shoe, but did they really have to tell you, the audience, that they found her shoe?
We've met before, haven't we?

I'm wondering more about how the cops didn't find the shoe that the sister lost while getting taken. That should have been an obvious find and hint that she didn't just run away.

the ending sucked ass.. the rest of the movie wasn't that much better!

I like how you just make up your own rules, your own story, pretend that the film must be following them, and then say that it's a plot hole when that's not the case.
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Damn, just saw this and I didn't know that thing was a fetus, I figured it was a head, it was kind of blurry and I couldn't make out the form, but a fetus is more gruesome and would make more sense since the sister was pregnant. Still, I thought this movie was pretty good and it gave me quite a few good scares without having to resort to loud noises, which is excellent in my book.

After reading all the replies I've come up with an alternative motive.
Perhaps Callies demand for a trade was not appreciated by the troll, & to show her that not only is she in no position to demand anything but also to note that what is and isn't a sufficient trade is determined by the troll itself, it returns the fetus as basically a "yeah well, beep you" and then takes both Callie & the fetus to the Underneath..
Just a thought.

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