A serial rapist stalks the streets of Scarborough and police call in the FBI. Profiler Gregg McCrary sees a pattern of escalating violence and worries the suspect will resort to murder. When teenage girls turn up dead, his worst fears are confirmed.

A DNA hit links the Scarborough Rapist to murders, exposing a killer couple. The wife claims abuse and testifies, but home videos suggest she's just as guilty. Investigators uncover their dark past, including her sister's death.

A woman withdraws $350,000 from a small-town bank, then passes a note saying she and her husband are being held at gunpoint. The clock is ticking as the FBI and local authorities race to rescue the couple before the kidnappers kill them.

A serial killer is strangling prostitutes across Europe. Austrian police and the FBI profile him, linking the crimes to L.A. He taunts victims' families and vanishes just as authorities close in.

The murder suspect is revealed to be a journalist reporting on his own crimes. He travels to Los Angeles, where more prostitutes are killed. As police close in, he flees to Miami with his girlfriend. U.S. Marshals track him down.

At a casino in Lake Tahoe, a bomb threat leads to a tense FBI mission. Unable to defuse the complex bomb, agents detonate it safely-but it destroys the hotel. As the FBI investigates, they uncover surprising connections to a gambling addict father.

In 2003, a disguised man robs the Xerox Federal Credit Union, killing one and injuring another. The case goes cold until 13 years later, when new DNA testing and a fresh tip bring a breakthrough, leading to a shocking resolution.

In rural Oklahoma, two young girls are found gunned down. After two years with no leads, the FBI profiles the killer, believing the cold-blooded murderer is a local who used two guns to execute the girls-and will likely kill again.

When a woman from a small town in Oklahoma goes missing, state and FBI agents wonder if the suspect in that investigation fits the profile of the killer in the case of two young girls shot dead at the side of a country road - three years earlier.

When a drug dealer reports extortion by a New Orleans police officer, the FBI launches a full-scale investigation into dirty cops. But the sting turns deadly when wiretaps pick up threats to an undercover agent and a cop ordering a hit.

The FBI teams up with Massachusetts State Police to infiltrate, disrupt, and dismantle the extremely violent MS-13 gang network in Greater Boston. They get a break in their case when a recently deported Salvadoran man agrees to become their informant.

The FBI's investigation into MS-13 in Boston is complicated by an informant's unsanctioned crimes.