Danny, Erin and Frank work together to seek justice when the main suspect in a rape case is protected by diplomatic immunity.

Danny investigates when a doorman at a nightclub is murdered; Frank makes a decision about a former partner's future.

Danny and Jackie investigate the cut-throat world of fashion after Linda's runway model niece and a reporter are poisoned at a fashion show.

When Danny is put on modified assignment after an incident in which a cop--who failed to identify himself--is shot, he faces Internal Affairs investigators, who are looking to his state of mind on that day for further implications.

Frank deals with a political crisis after Jamie and Renzulli are injured by a church security team that refuses to let them enter a religious center in response to a 911 call.

On the way home with his family, Danny hits a man with his car who is fleeing from a gunman, and his family gets caught in the crossfire when Danny fires his weapon at the gunman. Frank deals with 9/11 guilt from impending loss of a friend whom he worked alongside at Ground Zero.

Danny is put in a difficult position when a gun linked to a robbery is brought in to the NYPD’s gun buyback program. He must decide to either arrest the suspect or follow the no questions asked rule.

Frank must race to stop a biological weapon attack on New York City, while keeping it a secret from his family during their most sentimental holiday, Mother’s Day. Meanwhile, a long-standing conflict between Danny and Jamie comes to a head.

A dangerous criminal from Danny's past comes back to seek revenge and kidnaps Jackie. Meanwhile, Jamie meets his new partner, while a young officer is shaken after he accidentally shoots an innocent man.

When two motorists driving gas-guzzling cars die at the hands of a sniper, Danny and Kate are put on the case of what the city believes is the work of a radical environmental serial killer. Meanwhile, a bicycle accident sends Danny’s son Sean to the hospital with a life-threatening injury.

Erin and Danny investigate a cold case of a girl who was attacked by her rich and powerful boyfriend, who was never convicted. Meanwhile, Jamie’s friend brings a lawsuit against Danny’s friend after an injury at a pick-up basketball game.

Danny blames himself when a young woman commits suicide because he had made a promise to her in the wake of her parents' deaths. Meanwhile, violence involving a gang at a housing project erupts and affects the Reagans.

A teen girl dies after she is seemingly pushed in front of a subway car by a homeless man; Frank is irritated by having to meet with the new inspector general (Bebe Neuwirth).

Danny’s loyalty is tested when he is assigned to the case of a childhood friend, Mickey, who is under investigation for having ties to an infamous mob family. Meanwhile, Frank gets word that crime is on the rise due to a recent judicial ruling about the legality of the “stop and frisk” policy.

Danny and Baez search for teenager who have been randomly punching unsuspecting people in the head, including a pregnant woman; Frank worries that promoting an officer will be viewed as favoritism.

Frank is put in a difficult position when Danny is charged with using excessive force. Jamie brings homeless man to the hospital.

Danny and Baez investigate the death of an elderly woman who was shot in her home by a stray bullet. Also, Frank faces ridicule from his department when he disciplines a disrespectful cop, and Erin steps in to help her detective, Anthony, find a legal solution to a case that’s personal to him,

Frank is left with minimal information to find a missing boy when a conflicted priest who could help won't break the seal of confession. Also, Danny and Baez investigate the death of a prominent New York City socialite with a secret life, and Jamie and Eddie attend a wedding together.

While investigating the murder of a man who killed a mother and son years earlier while driving drunk, Danny and Baez are torn between doing their job and finding justice after discovering the connection between the suspect and the victim.

After Reggie Wilson, a witness in a former case of Erin’s, asks her for help shutting down a drug operation in his apartment building, she makes it her mission to make the building safe for his family. Also, while investigating a teen’s suicide, Danny and Baez uncover information that suggests the death was a homicide, and Frank looks into potential misconduct within the Mayor’s office.

Danny and Baez work the case of a detective who was gunned down prior to testifying against a career criminal. Meanwhile, Frank personally investigates when Garrett is attacked by a S.W.A.T. team outside his home; and Erin brings in a confidential informant against Anthony’s wishes.

Jamie and Eddie ask Erin to drop old charges against a man who bravely rescued a woman from a local hostage situation; Danny and Baez work a case involving car thieves and discover the leader is a mobster they've dealt with before.

Danny and Baez investigate the murder of a man who was living a double life with two separate families, and Anthony tries to resist when Erin asks him to help investigate his old partner, whom she suspects of stealing drug money. Also, Frank deliberates between two candidates for the chief of transit position.

When Danny resorts to asking his incarcerated archenemy, Victor Lugo, for help locating a dangerous criminal who escaped from prison, Lugo refuses to assist unless he’s allowed to accompany them on the pursuit. Also, Frank subtly tries to convince Jamie to take the sergeant’s test, and Erin’s plan to go on a date with her ex-husband causes friction between her and Anthony.

While investigating a case involving a woman who shot her husband while she was drunk, Danny's instincts tell him there is more to the story. Anthony ignores Erin's orders to drop an assault case. Frank holds an emergency drill for his inner circle. Jamie and Eddie navigate their changing work-life dynamic

A video surfaces of cops being harassed by a group of people at a housing complex, which leads Frank to order a raid to round up anyone with an outstanding warrant, against Garrett’s advice. Danny is approached by a woman he put in jail who asks for his help keeping her brother out of trouble. Nicky’s new boyfriend has ulterior motives.

While off duty, Danny encounters a gas station robbery in progress and is forced to use his weapon, leaving him shaken and his family and co-workers concerned. Also, Eddie apprehends a turnstile jumper who pleads for leniency by offering information on a missing weapon that's vital to one of Erin's cases, and Frank learns that a top officer in his department has a dark past.

As Jamie and Eddie's wedding day approaches, Frank worries about the toast he'll deliver at their rehearsal dinner. Also, Erin interviews a witness whose story leads her to doubt Eddie's honesty, since she took his initial statement, and Danny and Baez unravel the complicated love life of a young homicide victim.

Frank takes one of Jamie’s cases to heart when it involves the suspicious death of his friend’s, FBI Agent Wilson Ortega’s, terminally ill wife. Also, after demanding more meaningful cases, Erin receives an unsolved robbery case that proves to be impossible to crack without help from Anthony, and Danny and Baez uncover the shocking truth behind a puzzling assault claim.

After a woman is found dead at a men's-only club, Danny and Baez investigate if her death was an accident; Frank hears about an alleged affair between the chief of Internal Affairs and the spouse of another member of law enforcement.

Frank and Garrett devise a plan to convince Mayor Chase to work better with others in order to properly run the city, and Danny and Baez try to track down a perp who vandalized several NYPD vehicles with anti-cop graffiti and made threats against officers. Also, Erin is shaken after she's in a car accident, and Eddie and Jamie argue about whether they should keep a stray dog who leads them to a crime scene.

Danny and Jamie combine forces to convict a notorious drug lord, as Erin nervously awaits the Governor's selection for the new District Attorney. Also, Frank and his grandson, Joe Hill (Will Hochman), face a difficult decision as they navigate their new and complicated family ties.

Baez confides in Danny and asks for his help in proving her innocence after she finds a corpse in her front yard. Also, Erin struggles to find a peaceful solution when she receives harsh case notes from her boss, Jamie and Eddie butt heads over the handling of a young cop’s punishment, and Frank makes his whole team attend therapy after Gormley exhibits troubling behavior.

Frank and Garrett quarrel when Garrett refuses to walk back a quote he provided to a local newspaper. Also, Danny and Baez discover a connection to a feud between local residents and city-sponsored hotels for the homeless while investigating a murder, Anthony is mistaken for a mafioso and Eddie pressures Jamie to take a love language quiz.

Danny and Baez's attempts to find who assaulted a shop owner are hindered by the community's refusal to cooperate; Erin's suspicions about her boss rise; Gormley, Garrett and Baker are threatened by a new staff member.

Danny pursues a con artist pretending to be the legendary singer Jimmy Buffett; Frank investigates an impressive police captain who is using her badge to get free wares from local stores.

Frank, Baker, Garrett and Gormley experience feelings of guilt when Detective Angela Reddick (Ilfenish Hadera), an officer they briefly worked with at 1PP, is shot after Frank reassigned her for not meshing with their team. Also, Eddie, Danny and Baez investigate a man’s murder after Eddie and her partner respond to an altercation between the victim and a neighbor, and Anthony finds himself at a crossroads when he’s offered a promotion that strains his relationship with Erin.

Danny crosses paths with a criminal from a previous case when he investigates a gang attack with a shocking motive; Frank and Mayor Chase butt heads over an off-duty cop who goes too far making a political statement.

Danny reunites with Mickey Patrick, his childhood friend and a former criminal, who comes to him for help finding his missing fiancee; Anthony surprises Erin with one last stakeout before her run for district attorney.