To help capture a serial rapist-turned-killer, FBI Special Agent Don Eppes recruits his genius brother Charlie, who uses a mathematical equation to identify the killer's point of origin by working back from the crime scene locations.

Charlie accurately predicts where a band of bank robbers will strike next. But when Don and his team confront them, a massive shoot-out occurs leaving four people, including an officer, dead. The outcome disturbs Charlie and he retreats into the family garage to work out an unsolvable math problem that he also plunged into after his mother became ill a year earlier. But Don needs his brother's help and tries to get Charlie to return to the case.

Don and Agent Weston of the NTSB investigate eyewitness accounts of a mysterious unidentified object flying dangerously close to downtown Los Angeles that has raised concern of a terrorist attack. After Charlie is recruited to help with the investigation, it is discovered that the flying object is part of a new technology that could revolutionize air travel. But the investigation takes a turn when they learn that the lead engineer is found murdered.

Don uncovers a secret code that begins the hunt for a skilled and trained assassin, and the efforts by the FBI to save the life of a Colombian exile living in Los Angeles.

When a father is killed in a home invasion, Don and his team investigate the connection between the murder and a rash of robberies in the upscale community.

Don and his team investigate an anti-war bombing outside an Army recruiting center that resembles the work of a 1970s anti-war activist who disappeared 30 years earlier after being accused of planting a bomb that killed two people. Retired Agent Thomas Larson, who tried to solve the case 30 years ago, returns to help but questions Don's loyalty when it is revealed Alan knew the radical activist and participated in demonstrations with him, thus causing tension within the family.

An FBI investigation into a computer hacking scam that taps into a bank's system to gain access to the identities and financial assets of its customers becomes personal for Don and the Eppes family.

Don and the rest of the team investigate several attacks occurring on LA highways that may be connected.

The case of a dead minor league baseball player leaves Don and the team with more questions than answers. When Charlie discovers that someone has come up with a statistical analysis that can identify which of the players are on steriods, the case gets more leads...and a suspect.

Several area murders seem to be tied to voter fraud. Don, Charlie, and the team must find the killers before they strike again.

$50 million dollars in medical relief is up for grabs after the shipment is stolen. But there's a catch--someone other than the FBI wants to recover the shipment. Don and the team find themselves pitted against blackmarketeers in a deadly race for the supplies.

When a car crashes into a busy coffee shop, the team discovers the fatal act might not have been an accident.

The team investigates the theft of a graphic comic book.

In the season finale, Don and Charlie work together on a case that ends up with them going head to head about their personal beliefs, and one team member will walk away forever.

Two rock climbers in possession of a large stolen diamond are killed, and Don and the team hunt for the murderers; Charlie considers whether he should have his FBI clearance reinstated.

Charlie is forced to turn to his arch rival for help when a vigilante group goes after a career criminal.

Feeling guilty over the stabbing, Charlie puts his attention on finding a serial killer using math theories to help the team solve the case before another life is taken.

The team investigates a decommissioned air base after a woman is found dead there, but their investigation is interrupted by paranormal happenings.

After Charlie and Amita get married and begin preparations for their London adventure, they put a slight hold on their wedded bliss when they assist the team in helping Don track down the whereabouts of his gun after it goes missing.