Film Theory: The Aliens In Signs Aren't What They Seem...
1. The End
On the radio at the end, we hear that a ‘trinity’ of countries in the Middle East, the birthplace of Christianity, discovered a “primitive way” to defend against the attacking forces. Whether it’s the prayer that Graham refused to utilise or the Holy Water that Bo discovered as most effective - the religious connotations are hard to ignore.
The constant battle between science and God is not one that will be ended by this movie, but it is one that is given nuance by the interpretation of fate. We don’t know if all our actions are leading to something greater or if demons, or aliens for that matter, are real - but Shyamalan’s combination of all these things is at the very least is something to consider.