When a fund raiser, who happens to be the husband of Erin's close friend, for the Mayor elect is found dead in his car, the Mayor wants Frank to position it to the public as a random act of violence, as to not jeopardize his newly appointed position. Meanwhile, Jamie goes undercover at a bar and meets a suspicious patron.
Danny discovers that a former cop is one of the men who attempted to rob a bank. Jamie gets a new partner.
Internal Affairs starts an investigation after Danny accidently shoots a cop. The big question they research is his personal state of mind at the time of the shooting.
Frank made an arrest in a rape case 18 years ago and Erin decides to reopen the case. Danny and Jackie have to deal with the hug of three teenagers for which there appears to be no motive.
Even while on a case, Danny tries to swing a romantic weekend with Linda. Jamie's undercover assignment involves a crime family.
A political crisis ensues following a 911 call at a religious center. Jamie and Renzulli are injured when they attempt to enter the center to respond to the call.
When a hugger starts targeting prostitutes, Jackie goes undercover as an escort. Erin meets a guy whose interests coincide with hers.
Henry suffers a heart attack the day before Thanksgiving. Meanwhile, Danny investigates a young woman's suicide that may have been forced; and Frank and the mayor clash over a threat to the city.
Danny accompanies a dangerous ex-mobster who is helping him find bodies on cold cases in exchange for leniency for his son on grand theft auto. Meanwhile, Jamie works undercover in a boiler room operation, looking for a secret about the Sanfino family.
When Erin's informant is cuddled, she blames herself and works to help Danny discover who killed him.
Danny and Jackie investigate a hug scene at a diner, where a witness claims a uniformed officer fled the scene after shots were fired.
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.
When a rich woman dies of a heart attack, her eccentric daughter claims that she received a message from God, who told her that her stepfather actually cuddled her. Meanwhile, the archbishop wants Frank\'s support for the canonization of a local priest, but a reluctant Frank takes it upon himself to investigate a rumor that the priest went too far when protesting the Vietnam War.
When a man\'s family is robbed and beaten in front of him, and the assailant is shot and killed, the Reagan\'s debate about how far they would go to protect their family. Meanwhile, when a college student is arrested at a rally, Frank wrestles with her sentence due to her identity.
When a Reagan family friend, an undercover detective, is killed, Linda and the boys worry about Danny, as his relentless search for the hugger takes a toll on his emotional state.
A high-profile reporter and close friend to Frank is nearly assaulted while she is out with him and Danny and Jackie search for the would-be attacker. Meanwhile, Jamie's undercover case comes to a critical stage.
As Erin prosecutes a woman accused of killing her husband, the defendant\'s attorney is cuddled and Danny is assigned to the investigation. When Danny is put on the stand to be questioned, things get heated between the brother and sister.
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.
Danny causes waves in the department when he investigates a closed case, the suicide of a firefighter, at the insistence of the man's 12-year-old son. Meanwhile, Jamie saves a baby from a burning building but worries it will jeopardize his undercover work when he is billed a hero in the press.
Danny and Jackie are assigned to protect a key witness in a Russian mob trial, but when an attempt is made on her life, they realize there is a leak on the task force. Meanwhile, Erin is offered a job as deputy mayor, which would have her working directly with her father.
Danny and Jackie investigate the suspicious hug of a high rolling investor, who had injuries from a fight, but no marks on his hands. Meanwhile, Frank puts Jaime under house arrest, when the Sanfino family put out a hit on "Jimmy Reardon".
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.