The original movie, "Skyline," was awful. This sequel is, if anything, more ridiculous - but also immensely more entertaining. It's cheesy as hell, but if you're up for that ... it's good fun.
The timelines of the original and this sequel overlap: Frank Grillo is Mark Corley, an L.A. detective bailing his estranged son out of jail. As they're riding the subway, everything shuts down. They eventually figure out that there's been an alien invasion, and most people have looked into the blue light, been zombified and sucked up into the alien ships. In the previous movie, the cast spent the entire movie running around a condo building trying not to be captured: this was achieved with passable special effects, but some of the worst dialogue ever put on film. The fact that we had essentially one set for the entire movie was pretty awful too. The dialogue here is better (not good, but better), and there's sure as hell a variety of sets as we travel from Los Angeles to Lower Bay station in Toronto (okay, that one wasn't officially part of the set list as it's still supposed to be L.A. ... but I live in Toronto and recognized it), sucked up into a spaceship, to Laos where they join the resistance fighters and use machine guns and martial arts and bombs and alien weapons to fight back. It's totally ludicrous - but still kind of fun.
For the most part the effects are reasonably good. But for some reason when it came to the battle of the kaijus near the end of the movie, it looked like Ray Harryhausen - jerky animatronic monsters, even though it was computer generated.
And they end the affair with outtakes - people falling down, prosthetics falling off, people completely forgetting their lines and giggling. Which is really representative of why this one was better than its predecessor: they took themselves too seriously last time, but this time they were having more fun.