Now entering their third year on the job;these rookies have learned to overcome the sophomore curse -- that a little knowledge is a dangerous thing. With a little more experience under their belts;they're starting to realize that the uniform that's shaping their professional identity has also started to shape them as people. They're also starting to learn that sometimes;in order to define who you are;you must first sacrifice who you used to be... even if you're still figuring that out.
Andy faces a tribunal that will decide her reinstatement; a drunken driver (William Shatner) with a grudge against the police causes a multicar crash.
The theft of an armed police car tops the list of dangerous pranks as local schools wind to a close for the summer. While tracking down the stolen vehicle, Andy and Swarek pick up the trail of a hotheaded teen boy who robbed and violently assaulted a notorious local criminal - who happens to be his girlfriend's father. Andy and Swarek must find the armed teenager before disaster strikes.
Dov's world explodes into chaos when he walks in on a convenience store robbery in progress - and shoots a young black teenager, who may or may not have been armed. The tight-knit community erupts in outrage, as the ensuing investigation calls into question whether Dov used excessive force or acted too quickly. Filled with self-doubt, Dov is left to wonder if he operated within the guidelines or if he will be charged with murder, as 15 Division struggles to prevent a riot in the sweltering streets.
All hell breaks loose on Traci's first day as detective when a carload of young women from a bachelorette party slams into another vehicle, apparently killing the driver. When the police discover that the driver of the parked car was dead before the accident, Traci realizes that her "rookie" handling of the car crash may have compromised the pending homicide investigation. Meanwhile, as Gail and Chris work together on the case, Chris not only realizes he still has feelings for Gail but that he also has competition. Finally, when Traci and Andy uncover a secret the bride is desperately trying to keep, it's a race to find the murderer before he strikes again.
Andy's personal life turns upside-down when she answers a domestic disturbance call and the social worker on the scene turns out to be her long estranged mother, Claire, who abandoned her and her father 15 years ago. Now Andy must deal with her private issues as she works alongside her mother to investigate the secrets of a family in turmoil. Meanwhile, Sam, Nick, Chris and Gail are in a race to find the desperate mother and her two children before she makes a tragic mistake. And Detective Jerry Barber's badge may be on the line when a stash of guns he recovered ends up resurfacing on the streets.
A noise complaint at an illegal warehouse party leads Andy and Swarek to an injured John Doe, a homeless squatter who has been brutally stabbed. They apprehend a surprising material witness -- Oliver Shaw's 15-year-old daughter, Izzy. When Izzy disappears, the officers move into emergency mode to track her down. But her involvement in the crime nearly pushes Shaw over the edge - both as a cop and a father.
After the embarrassing loss of a key witness in an upcoming organized crime trial, the officers of 15 Division must turn to a man who claims he is a gifted psychic to help track the witness down. Having taken a leap of faith when his information checks out, they begin to suspect the man's motives... Is he a talented psychic or brilliant con man? The police are compelled to confront some hidden truths about themselves and their fellow officers.
A grad student's disappearance leads Andy and Nick to discover the woman's double life as a high-end escort. When a pattern of missing women emerges, Gail, who is physically similar to the victims, is sent in on an undercover sting operation. Meanwhile, Dov and Chris are following a different lead, and when they uncover the body of a missing woman, the case takes an even more dangerous turn.
The officers of 15 Division are forced to release a suspected predator for lack of evidence. But when Dov and Chris make a grim discovery -- a missing girl's body, hidden in a deserted ravine -- all bets are off. Detective Luke Callaghan returns to oversee the homicide investigation, and soon realizes this might be the work of a serial killer. When they learn that Andy has been assaulted and Gail violently abducted following the call girl sting, the officers rally in a race against time to track down Gail's captor before it's too late. Following up on a simple lead, one officer ends up directly in the path of the killer. Will it end with the ultimate sacrifice?
The officers are trying to move on with their lives in the face of a tragedy when they discover a police laptop has been stolen, containing sensitive information. They set off on a hunt to recover the computer and prevent any dangerous fallout. When Andy, Nick and Swarek uncover a drug informant who may have been compromised by the leak and when Sam suspects the informant's motives, it drives a wedge between Andy and Sam, unleashing pent up emotions.
When a death threat aimed at a local priest leads Andy and Nick to a neighborhood drug lord, the officers realize that they're navigating a delicate war zone and that the priest may be hiding some surprising secrets of his own. Meanwhile, Gail and Traci pick up one of the drug runners - a young girl whose refusal to be an informant compels Traci to make a major decision about her career. Chris and Swarek clash over what it takes to make a good cop, and Dov's new relationship takes a dramatic and dangerous turn.
Weeks of trials and tribulations come to a head when the rookies of 15 Division are left on their own and a frenzied night in the station culminates in a prisoner pulling a gun on Chris in cells. The ensuing inquiry has Internal Affairs looking for someone to blame. With careers on the line, the rookies reflect on the personal and professional choices that have led each of them to that night's events, walking a fine line between telling the truth and having each other's backs. Meanwhile, Gail is still trying to recover from her harrowing abduction, Chris is blindsided by a personal revelation, and Andy learns a secret about Nick's past.
When a violent child abductor escapes from an emergency hospital visit, the officers of 15 Division try to track him down before he takes another young victim. When Andy and Dov discover that the desperate man has snatched another girl, Andy and Swarek find themselves in a deadly standoff to save the terrified victim, resulting in a major emotional confrontation -- and a serious choice for Andy. Meanwhile, Chris' family obligations have him contemplating a transfer, and Traci and Gail each face monumental decisions regarding their respective careers.