The team investigates if 15-year-old whiz kid Ryan Wallace is missing of his own accord in order to execute his elaborate plan to bomb his high school.

The team's newest member, FBI rookie Elena Delgado, formerly of the NYPD, encounters a learning curve as she attempts to help search for missing 20-year-old Dina Kingston.

Alex is sent on her first kill mission. Birkhoff discovers the shell program that has been used to connect to Nikita in the outside world. Nikita is captured by Division.

At a home construction site, a body is found beneath a wall.

When Sal's gun is stolen, Nate & Sammy launch a manhunt to retrieve the weapon, only to make a disturbing discovery, a local gang is using military weapons to become a street army.

When jewelry thieves begin robbing Bel Air homes, Officer Ben Sherman breaks police policy and becomes personally involved because he knows one of the victims.

When Patrick Jane and others are taken hostage by an armed man accused of murder, Jane must think quickly to defuse the situation.

A young boy seeks help when his sister doesn't come home from work. Benson and Carisi suspect a woman's assault was prearranged by a third party.

At a home construction site, a body is found beneath a wall.

When jewelry thieves begin robbing Bel Air homes, Officer Ben Sherman breaks police policy and becomes personally involved because he knows one of the victims.

When Patrick Jane and others are taken hostage by an armed man accused of murder, Jane must think quickly to defuse the situation.

Alex is sent on her first kill mission. Birkhoff discovers the shell program that has been used to connect to Nikita in the outside world. Nikita is captured by Division.

Martin and Danny attempt to dodge a hail of bullets as a mercenary and his cronies try to kill their true target.

The team investigates if 15-year-old whiz kid Ryan Wallace is missing of his own accord in order to execute his elaborate plan to bomb his high school.

The team's newest member, FBI rookie Elena Delgado, formerly of the NYPD, encounters a learning curve as she attempts to help search for missing 20-year-old Dina Kingston.

At a home construction site, a body is found beneath a wall.

A young boy seeks help when his sister doesn't come home from work. Benson and Carisi suspect a woman's assault was prearranged by a third party.

When jewelry thieves begin robbing Bel Air homes, Officer Ben Sherman breaks police policy and becomes personally involved because he knows one of the victims.

When Patrick Jane and others are taken hostage by an armed man accused of murder, Jane must think quickly to defuse the situation.

Alex is sent on her first kill mission. Birkhoff discovers the shell program that has been used to connect to Nikita in the outside world. Nikita is captured by Division.

Captain Raydor's audit efforts focus on Detective Sanchez.

The first episode tells the stories of the women who went missing, and how the idea that Ireland had a serial killer at large struck fear into the local communities.

In 2006, D.C. resident Victor Zaborsky calls 911 and reports a friend being stabbed by an intruder in the home he shares with Joe Price and Dylan Ward; authorities find Robert Wone dead and soon believe the home’s residents are keeping secrets.

The long investigation into D.C. lawyer Robert Wone's 2006 murder continues, with no new leads in sight; prosecutors ultimately pursue unusual charges in hopes of solving the case and getting justice for Robert and his family.

Van Pelt's actions are called into question when a witness is murdered while she is assigned to his protection.