Danny takes a case involving a drug cartel member who he believes torched his house; Erin is given a promotion but finds herself in a challenging situation when both Danny and Jamie ask her for help with their investigations.
Gormley tries to locate a former NYPD detective he believes may be a threat to Frank's safety; Erin navigates office politics when she chooses to reopen a closed case; Jamie is transferred to a new precinct with a lot of problems.
Danny investigates a case involving a woman who shot her husband while she was drunk; Anthony defies Erin's orders to drop an assault case; Frank holds an emergency drill for his inner circle.
When New York City experiences a major blackout, police officers scramble to contain the resulting chaos; Frank uncovers some unpleasant truths about his department; Jamie and Eddie question the line between work and their relationship.
Danny and Baez investigate a murder attempt against a celebrated fertility doctor with a seemingly pristine reputation; Eddie must intervene in a Reagan family matter involving Danny's boys; Erin helps Anthony find justice after a date goes wrong.
Jamie clashes with Eddie and her new partner when they fail to intervene in a dispute at a convenience store; Danny and Baez investigate the death of a college freshman at a fraternity party; a sergeant accuses the department of reverse racism.
Things get personal for Danny when the drug cartel hit man responsible for torching his house resurfaces; an attack on an officer in the line of duty directly impacts a member of Frank's team; Eddie reluctantly introduces Jamie to her mother.
Erin and Frank clash over new legislation from the district attorney's office that undermines Frank's policies; Erin is at odds with Governor Mendez over questionable sex-trafficking laws; Danny risks his badge to protect a friend from losing his.
Danny considers taking a new, more profitable job after investigating the death of a wealthy man; Nicky tries to avoid involving her family when she is sexually harassed by her boss at her new internship.
Danny forces his brother-in-law to help Baez take down the mobsters he's mixed up with; Frank suspects his old partner is guilty of a crime; Jamie is approached by an officer who wants help getting reassigned from his undercover assignment.
A woman voices outrage over her son's unsolved murder; Danny re-examines the case; Eddie gets shot while on duty; Erin and her ex-husband face off in court; Frank deals with an angry police force after the mayor fails to defend it.
Danny and Baez race to find a missing girl who will die without her heart medication; Jamie and Eddie are on the wrong side of an investigation after engaging in a car chase; Sean wins an essay contest.
Danny resorts to asking his incarcerated archenemy for help locating a dangerous criminal who escaped from prison; Lugo refuses to assist unless he's allowed to accompany them on the pursuit; Frank tries to convince Jamie to take the sergeant's test.
Frank locks horns with a data-tracking company when it refuses to unlock a terrorist's phone that may hold information regarding upcoming targets; Erin obtains information about an impending murder from a shady source; a woman kidnaps a baby.
When a series of drive-by murders occurs after six wrongly convicted men are released from prison, Danny and Baez wonder if the murders were orchestrated by the men as an act of revenge; Frank combats feelings of guilt.