I've always had a weird phobia of aliens despite being super interested in anything paranormal.
This is the only scene in a movie to make me physically uncomfortable. The nonchalant reveal just took it to another level that a traditional jump scare wouldn't have.
They called the little girl an angel more than once.
Also see where he locked one in a closet and it couldn't get out. Don't know if that's a demon thing or not, but he couldn't see it's reflection in the knife.
It turns out that Shyamalan, in an interview from 2006, has confirmed this.
"You know what I said about giving a Dracula movie a deceptive title? That's what I did with Signs. That was a story about a war between Heaven and Hell. The aliens were demons and the people's dead loved ones were angels."
I had this whole theory built up about how the aliens were manifestations of the little girl's trauma and grief and everything was just happening within the town. All the stuff on the radio and TV was her using spooky kid mind powers unconsciously. That's why they were allergic to water: she has a weird thing about contaminated water glasses.
And then at the end he just hits the fucking alien with a baseball bat and the credits roll. What the actual hell.
Honestly, signs was the first movie I ever experienced terror from all the way up until the end and now I literally do not give a single fuck about that movie.
Turns out I have a fear of aliens walking in the distance. Or, well, had.
Signs both clarified and cured me of it at the same time.