There's a new boss who comes from IAD with a mandate to clean up the squad. Andy receives a dead rat in the mail. John is heading off the rails. A doctor is found dead, and linked to a man who had a sex change.

The detectives tie the death of a pregnant woman to an adoption scam; Medavoy and Jones interview a woman who claims a masked assailant stole her valuable ring; and someone poisons Sipowicz's beloved fish.

When a convicted rapist is found shot to death, his victims become suspects in the murder investigation; and Sipowicz searches for answers when a stranger targets Theo as he walks home from school.

The detectives investigate the death of a phone-sex operator and the kidnapping of a wealthy man's son; and Clark's tryst with a murder suspect is used to derail the prosecutor's case.

After being shot outside a bar, Sipowicz discovers the identity of the person who's been harassing him.

While investigating a random stabbing, Sipowicz becomes obsessed with his own mortality after he's nearly gunned down by a murder suspect; Medavoy takes a job as a bouncer.

The detectives protect a scared witness testifying in a felony murder trial; Michael's father wants to regain custody; Bale finds out about Medavoy's job at the bar.

A gunman tries to kill a witness after a mistrial is declared in the Simon Kerensky arson case; and Jones goes to extremes to stop Craig from adopting Michael.

Jones becomes a murder suspect after Michael's father is shot to death; and Ortiz and Murphy investigate a molestation case that might involve a priest; Medavoy gets his hearing in trial court.

A man who cared for his brain-damaged brother is found dead; Medavoy falls for a wealthy woman while investigating an apartment rental scam; Bale tries to nail a man who offered the detectives a bribe.

While investigating a murder, Sipowicz discovers a secret about Bale; and Ortiz and Murphy investigate a shooting tied to a talented up-and-coming basketball player.

A call-girl's death is linked to other murders involving women who'd gone through rehab; Ortiz and Murphy investigate the death of an artist who'd been carrying on an affair with a wealthy man married to two other women.

The detectives continue their search for a serial killer who targets alcoholics trying to get sober; and Clark and Jones investigate a homicide linked to a woman with whom Clark had a one-night stand.

The detectives search for a suspect who killed a businessman by blowing up his car; and Ortiz and Murphy investigate the beating death of a student.

The detectives investigate the smothering death of an elderly man married to a voluptuous woman in her 20s; and a state judge pressures Medavoy and Jones to find out who poisoned her mother.

As Sipowicz settles into his role as sergeant, the 15th finds his absence unsettling, especially after Clark is teamed with a hair-triggered military officer on the murder of an Army man. Meanwhile, Jones and Medavoy's search for a missing homeless man leads one of them to a bold move.

A squad member is shot while storming an apartment; Clark and Jones investigate the bludgeoning death of a woman whose wealthy husband was going to finance a friend's salon business.

Bale offers to recommend Sipowicz for the squad commander position; Ortiz and Murphy investigate the death of an Arab woman; and detectives search for the man who shot Bale.

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.