Danny and Baez investigate the murder of a college professor who was involved with a questionable scholarship program. Meanwhile, Danny learns that his father didn't tell him that the DA is investigating him for ethical and procedural violations.
An undercover cop in Danny's squad gets killed, and Frank is determined to find the murderer. However, things get complicated when the victim's secret is unearthed. Elsewhere, Nicky turns to Jamie as she looks for an ex-classmate living on the streets.
In the fifth-season opener, Baez gets injured while escorting confiscated drugs, so Danny goes after the drug cartel responsible. Elsewhere, a lieutenant with a commendable record engages in controversial behavior, putting Frank in a difficult situation.
Danny and Baez temporarily get new partners because an outed cop's partner won't ride with him. Elsewhere, Jamie and Eddie try to snatch a collar from an arrogant detective; and Frank's statement on equality in the police force alienates the Archdiocese.
An ex-mobster agrees to help Danny find bodies linked to cold cases in exchange for leniency for his son on grand theft auto charges. Meanwhile, Jamie works undercover in a boiler-room operation in order to uncover secrets about the Sanfino crime family.
Jamie refuses to shun a cop who testified against her partner, earning him disapproval from Eddie and other officers. Elsewhere, Erin and Danny get into a dispute when a closed case leads to a new murder; and a sports celebrity visits Frank.
A thief is shot and killed after robbing a family and beating them, which makes the Reagans ponder how far they would go to protect their loved ones. Meanwhile, Frank struggles with charges brought against a girl arrested at a rally due to her identity.
Danny's emotional state causes concern for his wife and kids when he relentlessly searches for a killer who murdered an undercover detective. The case is personal for Danny because the victim was a Reagan family friend.
Erin and Danny face off in court when he is put on the stand in a murder case Erin is prosecuting, which centers on a woman accused of killing her husband. Danny gets involved when the defendant's attorney is murdered, and he investigates.
Danny faces a moral dilemma over whether to arrest a suspect who may be linked to a robbery. The difficulty arises when the man brings in a gun used in a theft. But Danny isn't allowed to question the man due to the NYPD's gun-buyback policy, which doesn't (more…)
Danny reopens a closed case in which a fireman's death was ruled a suicide. His decision causes upheaval in the department, but Danny reinvestigates at the insistence of the dead man's 12-year-old son. Meanwhile, Jamie rescues a baby from a burning buildin (more…)
An international felon keeps getting away with murder, but Frank and Danny set out to stop him. Meanwhile, Erin considers going into private practice in order to pay for Nicky's college; and Danny gets off on the wrong foot with his new boss.