Five young and ambitious rookie cops continue to navigate the emotional trials and tribulations of their professional and personal lives. Last summer these rookies hit the streets for the first time with their training officers and learned how to walk the thin blue line. Now the training wheels are off. More experienced, they're ready to kick some serious butt. But these rookies are just beginning to realize there are no shortcuts to being successful at this job. And when you're a rookie officer, a little knowledge is a dangerous thing, as they discover.

As a full moon hangs over the city, the rookies are unnerved by a series of strange occurrences. While investigating the bizarre theft of three severed heads from a medical lab, Andy and Swarek track a disturbed man whose obsessive behavior makes him suspect. In an effort to protect the life of a young woman who may be the next target, Andy places herself - and, inadvertently, Luke - in a potentially fatal situation.