This is one of those shows that start out as your basic crime story but turns out to be a melodrama after all. The crimes they worked on are quite intriguing. The investigations, though, are sloppy and the police are either lazy and promotion-hungry or just plain lucky. Even the cold case squad members don't have excellent investigative skills. I guess the writer really wants to show to the viewers that the transmissions are the real hero in this story. Everyone else is just a tool --- the self-righteous profiler, the kind-hearted cop who always cries, and the grieving squad leader. The good thing is that there is a clear rule about the impact of changing the past that is established early in the show. Even though there are a lot of awkward dialogues, ugly crying and cliches about cops, overall acting is really great. Even the lazy, conniving cops are so convincing i had to keep myself from throwing the remote.