Spoil ending

The story started off very well. New exciting plot, interesting characters. Until episode 3, it started to get a bit boring but still exciting enough to keep watching (maybe because I'd like to know what the ending would be). The worst was the last episode when all the developed thrilling story went down hill...

- Evil grandma was so hard to die when everyone died so easily. She kept coming back to life it's annoying.
- How could police let evil grandma pointed a gun at people?!? In reality, they would have already shot the grandma to keep people safe.