It also showed how humans were forced to build an unpenetratable city to keep the remaining human survivors inside while the others went out to fight with the zombies, aliens, and traitors.
At the end, it showed how Commander Leng had used herself as a sacrifice to buy time for the city to lock down and migrate to another space. It ended with showing how Commander Leng had something powerful that had been implanted in her body when she had gone to extract her memories and consciousness to destroy everything in the world.
The zombies, the aliens, the traitors, they had all perished.
Unfortunately, some had smuggled themselves into the city together with some things from the alien realm and now, the new world was facing the same situation again.
