In the wake of a deadly standoff with a mysterious, yet, brilliant bomber, Don and Charlie discover that he was poisoned to keep him from exposing a shocking secret that will change the FBI team forever.

When thieves hijack a truck filled with valuable medical supplies, $50 million dollars intended for a relief effort in Zambia and two aid workers, the FBI races a second violent crew intent on getting to the goods first.

Don and the FBI uncover a possible terrorist attack on Los Angeles that targets the city's water supply.

Don believes that a death row inmate has an ulterior motive when he suddenly wants to confess the whereabouts of bodies he buried during his days as a hit man for the mob.

While on the hunt for a serial letter bomber, Don and Charlie disagree over whether a suspected bomber, who had eluded conviction years earlier, is the person responsible for the latest murder.

When a small plane mysteriously crashes, Charlie tests the flight computer and uncovers the truth behind what brought the plane down.

Charlie tries to connect a series of murders to a voter fraud conspiracy and must track down who benefits the most from the rigged elections before more people die.

While Don is unreachable at a therapy session, the FBI and Charlie try to find the son of a music mogul whose kidnapper threatens to kill the boy if he is not paid a multi-million dollar ransom in one hour.

When a competitive mixed-martial arts fighter dies suspiciously in the ring while training for a championship match, the victim's sparring partner, who also happens to be friends with David, becomes the prime suspect.

Don and the FBI re-open a 17-year-old unsolved case when the badge of a missing LAPD officer, who is presumed dead, is found at a construction site.

Don and his team investigate a rash of deadly restaurant robberies.

When a multi-million dollar racing yacht sinks during a race, Don and his team are called to investigate after the treasure hunt to find the wreckage turns deadly.

Don and his team search for the fundamentalist leader of a polygamous sect who is on the FBI's most wanted list for committing numerous crimes, including rape and murder.

Don and Charlie try to catch a serial killer who is seeking revenge against Internet sexual predators who prey on young girls they meet in chat rooms. Larry launches on a mission to the International Space Station on NASA's Space Shuttle.

During the murder investigation of a state senator, Don and his team discover a plot to exact revenge on the individuals involved in a government sponsored behavior modification project.

Don and his team investigate a trail of illegal waste disposal after a sinkhole, which collapses in a school playground, kills an elderly woman and injures several children.

Don and his team investigate the death of a minor league baseball player to determine if it was an accidental overdose of steroids or a homicide.

When a series of blackouts occur in power stations leaving Los Angeles in the dark, Don and his team must determine if it is an accident or the work of terrorists.

When Don and his team investigate a murder at a horse track, they stumble onto more than just a plot of betting on fixed races.

Don and his team must determine if a shooting on the freeway was a random act of violence or the work of a serial killer preying on the citizens of Los Angeles.

When an interpreter working for the Chinese consulate is killed in an apparent hit and run accident, Don and his team uncover an unlikely connection to the Department of Justice.

When a painting worth millions of dollars is stolen from a museum just before it is to go on tour, Don and his team must track down the thief, believing it is part of an insurance scam.

Desperate to rescue their fellow agent, Don and his team close in on finding Megan, who is being held hostage by a disturbed teacher on a vicious crime spree.

While Don and his team are faced with trying to capture a 30-year-old teacher and her 17-year-old boyfriend/student who are on a violent cross-country crime spree, one of their own gets caught in the crossfire.