The Best Episodes Written By Siobhan Byrne O'connor

Cruz and Santiago try to track down a gang member who murders witnesses to his murders. Grace finds her mother, who doesn't seem to welcoming.

Goren and Eames uncover a deadly web of secrets when they investigate the murder of a prominent socialite's granddaughter.

Eames re-opens the case into her husband's murder.

Logan jeopardizes his and Wheeler's careers when a priest convinces him to re-open a murder case that's over a decade old which involves a politically-aspiring ADA who will stop at nothing to keep the truth buried.

After getting a match from an unknown relative from a DNA network, Sean Reagan does some detective work to figure out who this mystery person might be. Frank gets a personal request from a woman to transfer her son to a safer assignment. Danny seeks to uncover the truth behind the murder of a key witness in one of Erin's cases. Eddie begins to think about having a child after she and Jamie discover a newborn left outside their precinct.

Eddie and Jamie deal with a domestic violence case associated with an investigation lead by Danny and Baez. Frank and his friend go on a mission to avail themselves to an unfiltered look at the city. Erin is presented with a surprising offer.

Erin and Anthony clash when Anthony's daughter is the sole eyewitness to a fatal shooting. Frank wants to punish an off-duty cop for his inaction during an armed robbery. Danny and Baez investigate a violent mugging.

Danny and Baez team up with Danny's old partner to find a copycat killer. Frank and Mayor Chase battle over how best to handle the city's rising homeless population.

After someone breaks into Luis Delgado’s home and kills his wife, Luis and Danny team up to take down the vicious murderer who may also be responsible for Linda’s death. Frank finally meets Eddie’s mother. Jamie and Erin are at odds after Jamie seeks her help charging a man who confessed to him while under the influence.

Danny becomes the lead hostage negotiator when an informant in a large drug case holds Erin at gunpoint inside the courtroom.

Baez gets injured while escorting confiscated drugs, so Danny goes after the drug cartel responsible. A lieutenant with a commendable record engages in controversial behavior, putting Frank in a difficult situation.

Danny and Baez search for a Marine veteran who may have PTSD. A woman seeking justice for her murdered daughter catches Frank off guard during a press conference.

Danny takes on a personal case involving a drug cartel member who Danny believes is responsible for torching his house. Erin is given a promotion in the DA's office but finds herself in a challenging situation when both Danny and Jamie ask her for help with their investigations. Frank and Jaime have a disagreement when Jamie refuses to stop riding with Eddie.

The Reagans band together to prevent Joe from being killed in the line of duty like his father when they fear that his cover has been blown within the gun-running outfit he’s helping the ATF bring down.

Frank causes family tension when he assigns Jamie to guard Danny after a hit is put out on him. Frank tries to stop his grandson from seeking revenge after he’s attacked. Eddie gets a hostile new partner.

Danny and Baez race against the clock to catch a serial killer targeting young women. Erin and Eddie clash when Eddie intervenes in a murder case and Erin's personal life. Frank must decide how to discipline his grandson.

When a key witness in Danny's case is killed just before testifying, Erin angers Danny by enlisting Anthony to help him find the killer. Robert Lewis tries to force Frank to publicly support the Attorney General's investigation of the use of excessive force. Eddie and Jamie get the call for an attempted suicide.

Just before Danny is to give witness testimony at a Peruvian drug lord's murder trial, Linda is kidnapped. This drug lord has a history of intimidating witnesses.

Shockwaves ripple through the Reagan family when Danny discovers that their newest family member Joe is working undercover for the ATF to bring down a gun-running organization.

Jamie and Joe search for an undocumented teenage girl who has been sex-trafficked. A woman in witness protection is murdered. Frank calls out the District Attorney's office for instituting a new rule that classifies armed robbery as a misdemeanor.

When Danny and Kate come up empty-handed with leads for a shooting, Linda helps make a break in the case when she overhears the victim telling his priest who is responsible. Meanwhile, Henry is mugged at an ATM, which sends Jamie into a rage as he tries to track down the assailant.

Frank is put in danger when his dinner companion, mob lawyer Angelo Gallo, is shot. Danny is a juror in a murder trial.

A woman dies after undergoing plastic surgery, so Danny and Baez try to figure out what happened. Frank asks Jamie to solve a cold case. Erin explores the world of speed dating.

Frank is taken by surprise during an on-air interview with Erin's boss. Danny and his new boss clash as they investigate a drive-by shooting. Jamie and Eddie help out detectives with an apparent suicide.

Evidence against Danny surfaces when the attorney general's office reviews his shooting of a serial killer. Jamie and Eddie deal with a high-profile drunk driver. A slain cop's widow asks Frank for a favor.