The series ends as Lupo and Bernard try to locate a blogger who threatened to blow up a school, but the teachers' union hampers the probe. Van Buren's personal issues become a public affair. Olympic star Lindsey Vonn appears as a union employee.
The death of a young socialite points Lupo and Bernard toward the victim's cousin, and the ensuing investigation exposes a hefty inheritance, a secret romance, a fraudulent adoption and an unborn child.
A model's body is set ablaze in an alley, kicking off an investigation that forces Lupo and Bernard to retrace the steps of two party crashers who made an appearance at a political event. Meanwhile, Lt. Van Buren faces health-care woes.
A global-warming symposium becomes a crime scene after a scientist is poisoned and collapses during a speech. Detectives Lupo and Bernard initially suspect rivals from his field of study, but a messy custody battle points the investigation toward the victim's family. Tammy Blanchard, Tony Hale.
A man shoots four police officers to death, and the investigation reveals a protective mother and evidence that the victims may have known the shooter. When an arrest is made, the ensuing trial pits cops and detectives against the prosecutors.
Cutter takes on his mentor, Emily Ryan (Amy Madigan), when she tries to overturn the conviction of a man found guilty of a hate crime, and a secret from Cutter's past may affect the trial's outcome. Lisa Klein: Anna Chlumsky.
A young woman's body is found in a hotel food-service cart, and the murder investigation turns up superficial evidence implicating a medical student who may be using a research project as a ruse to commit crimes. Ray Backlund: Timothy Busfield.
Detectives Lupo and Bernard probe the murder of a high-school student whose body was burned in a parking lot, and the investigation uncovers a shocking cell-phone video, a shady educator and phony alibis. Moses: Aaron Shaw.
The slaying of a witness in a murder trial kicks off an investigation that exposes a conspiracy rife with affairs, black-market dealings and drug cartels, and creates a predicament for ADA Connie Rubirosa and the remaining witnesses.
A fatal drunken-driving accident may be more than what it seems when a suspicious nasal spray is found at the scene. In the course of the investigation, Detectives Lupo and Bernard turn their attention toward the victim's boss (Rich Sommer).
A doctor who performed late-term abortions is found slain at a church, and the man's wife accuses a pro-life protester of the murder. Meanwhile, Lt. Van Buren receives troubling news, and Connie deals with a moral crisis.
The death of a mother of 10 adopted, disabled kids kicks off an investigation that exposes an affair and a bid for reality-show stardom, which caused tension in the household. Larry Johnson: Jim Gaffigan.
In the 20th-season opener, a war veteran's body is found in a university parking garage, and the subsequent murder investigation leads Lupo and Bernard to a law professor (David Alan Basche) who once worked for the Department of Justice. Greg Tanner: Creighton James.