As he begins his new job as squad commander, Sipowicz disobeys orders and keeps a murder investigation open... even though a Japanese man with diplomatic immunity has confessed to the crime.

Simone's recovery is hampered by a chest infection. The doctors differ in their opinions of which treatment to use. Sipowicz's ex-wife turns up at the station, drunk and asking for his help.

After a shooting at a bar, Simone and Sipowicz are sent to the hospital and find that they know one of the victims. The whole squad is involved in the hunt for the killers.

The child of a rich family goes missing. The father suspects Israel, a local vagrant, of kidnapping him. Sipowicz has other ideas. In another case, a jewish girl is found raped and murdered on a bridge. Later, a young woman is caught using the murdered girl's credit card. Medavoy, Martinez and Russell piece together the information.

A murdered boy's father insists that a homeless man is guilty. The mother takes Russell into her confidence. Simone and Sipowicz hunt the killer.

A woman is found beaten to death and left in a wooden crate. Simone and Sipowicz trace her family. Medavoy and Kirkendall hunt for the shooter of a Car Services worker. Russell is called to the hospital, where a 6-year old boy has died. His parents claim it was an accident.

A mother and 5 year-old child have been shot dead in their apartment. Simone and Sipowicz suspect that a previous break-in may be connected to the killings and that ADA Cohen might be able to help them find the killer. Russell and Kirkendall search for a missing child and trace known paedophiles in their hunt for the abductor. Sipowicz's doctor gives him some good news and good advice.

As Simone's condition worsens, Lt. Fancy makes a request to the Uniformed Officers to be aware of the need for a usable heart. Simone's colleagues have to occupy their minds with the case of an old lady found hacked to pieces in her apartment. Of her two sons, one doesn't seem to care about it and the other is too full of drugs to understand what has happened. Sipowicz's mood gets him into a fight.

New squad member, Danny Sorenson, arrives and gets sent to a drive-by shooting, with Sipowicz. The rest of the squad, including Russell on her first day back at work, attend another shooting. The two incidents are related and cause friction between the two teams of investigators. ADA Costas asks Sipowicz to look into an old case she has reservations about.

Officer Dornan disrupts an AA meeting, leaving Sipowicz no option but to involve Lt. Fancy. Dolores' father threatens to take action against Malcolm Cullinan and gets PAA Irvine into trouble. Sipowicz and Sorenson search for the pusher who supplied Mike Roberts. ADA Cohen continues to express his jealousy, over Kirkendall.

Mike Shannon brings in a young boy who makes a confession to Sorenson. Sipowicz worries about his up-coming court appearance facing Sinclair. ADA Costas takes care of him. Dolores father attends the court hearing.

Sipowicz stays away from the squad and tries to come to terms with his loss. Evidence comes to light implicating Cullinan in more misdeeds and Sorenson turns to Sipowicz for advice. John Irvine is released from hospital, but is reluctant to return to the Precinct.

Danny has an emotional crisis; John Irvin helps in a case involving stolen antique clothing; Jill deals with a young woman with small children who steals because of her unemployed, abusive husband.

IAB is closing in on Jill. Jill explains the leverage Don has over her. Andy stays by Theo's side as he undergoes tests to determine if he has cancer. Changes are made in the department as fallout over Jill's ex-husband.

The detectives investigate a multiple homicide at a fast food restaurant; an addict gives his baby daughter to a drug dealer as collateral on an overdue loan; Internal Affairs reopens the Kirkendall case.

Sorenson is missing, and a stripper is found murdered in his apartment. Medavoy and Jones investigate a killing, but the suspect identified by an eyewitness has a seemingly unshakable alibi.

While investigating the murders of four teenage girls, the 15th squad discovers the shocking truth about the disappearance of detective Danny Sorenson.

Sipowicz is hailed a hero after killing the man responsible for Sorenson's murder. While Lieutenant Rodriguez teams up with another precinct to investigate the robbery of his mother, the squad investigates the murder of two men affiliated with NYU.

The squad investigates the murder of a young Chinese girl along with an alleged rape case. Irvin learns his father is dying. Clark tries to find a foster home for James Kilik.

The squad investigates two homicides: a gay man who hit his head after being punched out and another man shot on the street. Rodriguez is set-up by iab to take a bribe from an old friend.

Andy and Connie return from their week's holiday with Theo. A boy goes missing, and the squad is lead to a pedophile in the area. John meets with a lawyer about his father's estate.

McDowell and Ortiz investigate the death of a woman found in her apartment, where an ex-con neighbor is suspect. The investigation into Scott's murder points towards his friend. Andy thinks about the future. Rita meets John's father.

The temperature is rising. Andy receives a death threat. A prostitute is murdered, causing IA to look at John. A huge drugs and cash hoard is found. An elderly woman is found tied up and beaten.

Clark is placed under arrest after police find heroin in his car; detectives search for clues when a woman is beaten to death with a cordless drill; a murder victim's obsession with clean living may have led to his demise.

A meek and mousy young woman is found beaten to death on the floor of her apartment. Her brother- in-law is very upset but not about her death--he was paying her money to use her apartment for an extramarital affair.