Sometimes words just fail. This sounds like one of those really bad B-movies that tries to take itself seriously (again, see photo), but that only reinforces the comic aspect. In fact, presented as a comedy, this concept has a minimal chance of success (as opposed to the non-existant chance it has otherwise).
I can understand why a vampire and a zombie would be paired together on a police force since they can't feed on each other and that would keep the human cops at a safe distance. At least when they find those human criminals, they can eat together.