There really is no more need of a summary for this one because the original is still more than fresh enough in our memories. I was a huge fan of the first one until the end where I felt like they tripped all over themselves getting wrapped up in philosophical stuff too much. When I heard they were making a sequel I thought that this would pretty much be garbage. However, the fact that they left the style of the first one where it was an attack on the house and flipped it to people stuck out of their house trying to avoid getting "purged" was great and in all honesty I liked this movie more than the first one. They did another great job of "taking us" to this version of the world where the Purge exists. They kept you on your toes by having three different groups trying to survive before meeting up and trying to get through it all together. I thought it would slow down tremendously at that point, but they managed to amp up the crazy even more while showing so many different views on how to feel about the Purge.
I would definitely recommend people checking this out. If you liked the first, I believe that you will definitely like this one too. Again - I liked this one more actually. It's a violent/horror movie but is also really eye opening about how to look at things and what not government/political/humanity wise.