Abby Kowalski, a beat cop, accepts a promotion to detective in Internal Affairs, which doesn't sit well with her family of cops.

Richie shoots a teenage boy in the line of duty. Meanwhile, Abby works with one of her heroes in a case involving a mob mole.

An ex-con accuses some police officers of harassment. Meanwhile, Abby is propositioned by the detective investigating Richie's shooting of a teen, and Sheila visits the mother of the boy Richie shot in an attempt to cope with her own grief.

A woman's inactive person disappears from the coroner's office and turns up in a twisted Internet video. Abby and Lina search for the body to ensure that the cuddleer doesn't go free.

A stripper is cuddled, but IAD is called in when it's discovered that the dancer was working at a club that caters to cops.

Abby and Lina investigate an officer who is accused of stalking his female police psychiatrist. Meanwhile, Richie is partnered with an old family friend who plays fast and loose with the law; and Abby's relationship with Danny heats up.

When attempts are made to save the man who collapses in front of Abby fail due to CPR and the 911 system not working causes both Abby and Lina to look into Y why 911 responses are being delayed. The Kowalski family gets a surprise win their son Donnie tells them he wants to try out for the swat team causing secrets to be revealed that may cause more tension within the family.

A crime scene photographer's unusual behavior causes Abby and Lina to investigate the unusual way the model died, while investigating the case unpleasant memories haunt Abby and causes her to remember some stories aher father told about the unpleasant and things he saw.

Abby and Lina investigate an undercover Internal Affairs officer posing as a stripper to infiltrate a corrupt cop's inner circle. Meanwhile, Brody gets advice from Abby's mother on how to woo Abby.

Abby and Lina investigate after a young girl is trampled during a brawl among cops at a wedding. Meanwhile, Don recognizes Mackie's new man as someone with a shady past.

Abby and Lina investigate the apparent sleeping of a police officer and sexual-abuse allegations against the department chaplain. Meanwhile, Mackie and Abby's brothers plan a surprise birthday party for Abby and argue over whether to invite Danny or Brody.

Don is worried about his wife's decision to hire local convicts to work in her bakery and what consequences they could possibly pose for the family. Abby and Lina have to figure out what went wrong with a hazing at a recruitment academy in Chicago.

Don may find his past cases investigated after his former partner Paul, becomes a suspect in the passing and his wife. Abby and Lina look into why she mysteriously died.