In Signs, Bo's character at the end is described as an angel like, with her birth out of the norm. She also has an ability to somehow see the events to come with her supposed "dream" line in the beginning as well as brief mentions along the way (which backs up the idea that she could be an angel).  When she asks for a glass of water that one night following the site of the monster, she may very well be asking for it so she can use it in defense. Bo may know that water is the aliens' weakness all along. Why does she leave half empty glasses of water around the house? It looks to be a subtle hint that she understands what's to come at the climax. Once again, M. Night Shyamalan looks to have hammed in a very simple dialogue etched into our memory that has a bit more meaning than the eye can see.

Also, anyone catch the strikingly familiarity in that Bruce Willis' character in Unbreakable had water as his weakness too? And if you think about it, all three films (The Sixth Sense, Unbreakable and Signs) have the same theme of someone discovering their purpose in life. Which if you think about it, can be applied to Shyamalan's own life as well, as his career was far from gold in the early days before writing 6th Sense.

Adding to that, there's been some speculation about Bo not being human. But possibly, an alien herself. If you look at the facts, she doesn't like water but it doesn't appear as though she is hurt when she sips (a question to ponder). However, the sheriff states that the animals in the county have been acting funny and almost as if they smell a predator around. In the beginning segment, their family dog is scared but when Morgan and Bo are trying to have it drink some water out of its bowl, the dog attempts to attack Bo...as if she's a predator?

On the matter, 'deja_account' wrote...
"Also, building up on your theory that Mel's wife was an alien - could it be that the daughter (Bo) in fact was one? Witness her discomfort with water, or her out of ordinary birth -- could it be that this was the original twist that was discarded in a script rewrite?"

This seems to be a very intriguing concept to pose, as going into my April screening of Signs, my basic prediction was that Bo, or one of the family members, was in fact an alien and that the alien invasion was to bring back the one member that was "one of them". This theory came to play when I started thinking about 6th Sense and Unbreakable similarities in their twists months back. The Sixth Sense was told in the fashion where you thought the point of the movie would sit within our main character, Cole, when the trick was played on the character beside him, Malcolm. In Unbreakable, many of us expected a reason behind Willis not being hurt consistently when the twist was on Samuel L. Jackson, the character sitting beside our main character. So if you had taken that into consideration, you could have placed a theory that the switch wouldn't be played on Mel Gibson, but maybe a family member.

After viewing the full trailer following the preview screening of Signs, I realized that there's a moment where the sheriff in a voice-over explains that the animals are acting as if predators are around just when the dog is jumping up at Graham (as if he himself is a predator). It's as if 'deja_account' is correct and that maybe Shyamalan had originally written Bo as a full blown extra terrestrial not where she belongs. But instead of shoving the answer clear into our face, decided to change it around and hint at the matter to lead moviegoers into post-discussions. Which like Memento, is more effective than saying "here's the answer", as we talk and talk about it, trying to figure out the logics involved and if all the pieces match up. This is where the fun begins, as the filmgoers who love to discuss the meanings behind such films go nuts.

Also on the matter, the point that makes Signs different and more remarkable from the other two of Shyamalan's major releases is that this is much more open to interpretation and we have no straightforward twist brought to our attention. But more so, possibly hidden interpretations that can be found after investigating facts. Night could have followed through with another twist but doesn't walk the cliché route where he could be viewed to be predictable in the storytelling for those who picked up on his previous twist patterns.

I may very well be too "into" the details behind Signs, but I figure, might as well bring the ideas to the table for whatever they're worth, if anything at all. Adding to that, anyone pick up on Morgan himself being a little clairvoyant with something along the lines of "it's going to go into history books" line right before the newscaster says this? I talked with someone who claimed it was purely a joke, but you have to recognize that both children had moments of these psychic abilities. Along with that, Morgan and Bo are seen wearing (alien) tinfoil hats claiming "so the aliens can't read our minds". Is it probable that both children are in fact extra terrestrials of some sort and are serious when they don't want the aliens to know what they are thinking? Consider why the alien at the end grabs Morgan; because he is a good extra terrestrial and it's Judgment Day?

Merrill is also seen wearing a tinfoil hat for humor purposes, and whether or not he is "one of them" is a question to behold but nothing offhand appears to line up with the logics of that. And adding to that thought, it almost appeared as though Shyamalan may have inserted these subtle hints/clues behind laughter deliveries to hide the "donning" from filmgoers until the later discussions; almost like a shield. JPK mentioned to me that the script appeared a little staged, possibly cueing into the possibility.

Anyone notice the brief details in the introduction to Signs? It appears as though Graham awakes from a bad dream in the opening shot. This is just moments prior to when Bo asks him if he was in her dream too. Is there a connection (more of a rhetorical query, as I don't have an answer yet)?

As it is just coming to mind, it seems as both Unbreakable and Signs have the interesting similarity where both villains are seen in some sort of reflection in the first official spotlight. Elijah all grown up is seen through the art frame's reflection while the alien at the end of Signs is spotted through the television reflection.