Heads up, this movie was also released under the Title "Alien Uprising." I live in the States and that's how it is listed in my Netflix.
This movie is about a shadow invasion/conquering of earth by Extraterrestrials, where their goal is to minimize collateral damage. I.e. they don't want to destroy the world, only conquer it and rule over us. To this end, they disrupt communication networks to prevent organized resistance. Furthermore, a major threat to causing collateral damage is human panic. No communication prevents wide-spread panic.
The story follows 4 friends <PERSON>, <PERSON>, <PERSON>, and <PERSON>'s girl, <PERSON>, as they go clubbing, one picks up a girl, and the next day they wake up to find power, phones, radio, and TV all not working. On the second day, large flying saucers arrive over the cities.
Carrie (<PERSON>) is the girl <PERSON> (<PERSON>) picks up at the club at the beginning of the movie.
She also is an alien/extraterrestrial visitor.
The Aliens have been living secretly among us.
The soldier (also an alien) guarding the Chemist shop moves to attack and kill the girl who knew he had "the purple mark," presumably to conceal the alien existence. 829
<PERSON> attacks him, which could lead us to believe there are two factions.
The friends eventually wind up at <PERSON>'s (<PERSON>'s uncle) place (<PERSON>). <PERSON> is one of those ex-military, knows top secret stuff kind of guys.
At the end of the movie, the flying saucers (cylindrical ships) are locked into a space battle with pyramid shaped ships. We also the see soldier who was guarding the Chemist shop back to life. (Or at least a copy of him.)
So the way I see it, there are two possible endings here, which are ambiguous.
(Ending 1) When <PERSON> killed the Soldier in the Chemist shop, she knew she wasn't truly killing him. So when the fighter ships are destroyed, the aliens are destroying ships, but they are not losing any life as they stage this battle for our benefit. The Aliens staged a fake war so that humans could come out of the event feeling like they had won, when in fact, the aliens had quietly assumed power.
(Ending 2) The aliens are trying to do a shadow take over, but humans have built a massive fleet of space ships, copying technology that has crashed on earth over the years. As the movie concludes, the human space fleet is moving into higher orbit around earth, taking the fight to the enemy.
I think Ending 1 is much more consistent with the theme of the movie focusing on mankind's capacity for violence, almost as if the movie is passing judgment on mankind and pronouncing him unworthy to continue living.
I think you could probably come up with some other theories that fit the movie as well. It definitely is not the most clear ending in movie history. 829