When pure evil responds to the Arecibo message, a lowly NASA clerk must convince his superiors that planet Earth is facing doomsday, and nobody cares.

What I’m being promised here is a movie in which someone is trying to convince someone else.

The interesting part of the movie I (and probably everyone else) want to see is not the convincing but the action that will follow once they are convinced.

Or else, perhaps it’s a HIGH NOON in which the hero tries to rally support against the clock but ends up having to face evil himself.

Another problem, however, is that ‘doomsday’ is too vague, as is ‘pure evil’.

Plus, I’m afraid that most people don’t know what Arecibo means and won’t bother looking it up.

Perhaps try something along the lines of “When an evil extraterrestrial force responds to a message sent into space by humans, …” and then be more specific about the type of events that unfold.

Thank you Nir. You’ve just reminded me of one of my own key rules: the antagonist must never be faceless.

Initially, the antagonists can be the superiors (see JAWS) but ultimately there will be a standoff with the alien baddies and we need to know what sort of creatures they are and what exactly their plan is.