The movie shows clear logical every-day steps that allows a person to create a doomsday device
So imagine a 45 minute movie that gives any person, no matter ability skill or how 'sound of mind', simple instructions to create an all-powerful device that will certainly cause the death of everyone.
For instance, by knowing somehow a system of quantum mechanics that is beyond (or within) our understanding, the aliens say 'put a cup of x with a cup of y, add a dash of z, and you can make a black hole that will destroy the world'.
Now that everyone on the planet is armed by this simple knowledge, everyone now knows that at any time the world will end. This is now an extreme form of PTSD. Everyone knows that there is always one lunatic somewhere in the world, who could build the device and cause the planet now to collapse, killing you and everyone you love.
It now makes logical sense for your own survival, or even your duty, to go mad and destroy as much as you can, in the vain small chance that you can do so before some lunatic creates the doomsday device.
(Oh no... I have just created a basilisk :( May need to delete this answer to not give anyone crazy any ideas...)
Ok - I have undeleted my delete because I realised that if I haven't thought of this basilisk, someone else would eventually. So the only defence is to know about it... and prevent any person from making a movie like this.
I'm already going insane just thinking about this. We need worldwide laws on this now.