When the wife of a judge is killed the team investigates. And they discover that it might not be for the reason they think.

The team investigates a jewelry store theft where the robbers kidnapped the owner's wife and daughter.

A pop star is receiving death threats from an obsessed stalker but Charlie is convinced the letters are written by two different people.

Don takes under his wing the son of a murdered executive as the team and Charlie try to narrow down who's responsible out of a pool of six thousand or more.

When Don and his team find a strange code during a raid, Charlie suspects it is part of a plan to assassinate a Colombian exile living in Los Angeles.

When a death results from an anti-terrorism exercise Don and his team are called in, but they end up butting heads with the leader of the unit who refuses to halt further training exercises. Back at home, Alan has volunteered the house for the wedding of a girl both Charlie and Don had a crush on in high school.

Charlie searches for a link between robberies when the number of violent home invasions in an upscale neighborhood suddenly escalates.

Charlie finds a disturbing photo on a confiscated computer and pursues its origins.

A few apparently random cases of product tampering lead to a mountain man with a grudge, a pharmaceutical company and a conspiracy.

The murder of a young museum researcher sends the team on a search for a killer and a missing Native American skull.

Charlie seeks out an engineering professor to help him recreate a fire scenario to solve an arson case.

Charlie uses math to determine the killer of an undercover FBI agent.

Charlie and the team investigate a murder at a casino.

A crime scene drenched in blood leads the team to a form of human trafficking, and Amita to her past.

When a DNA synthesizer with terrorist possibilities is stolen from a university lab, Charlie and the team must find it before it leaves the country.

The bombing of a recruitment office puts Don and his father at odds, and brings an agent out of retirement.

A psychic helps to find a burial site of numerous illegal immigrants just across the California-Mexico border. Charlie and he battle to see who will come up with the location of another female migrant before she joins the other victims in the morgue.

After an Iraqi woman - in the US to film an interview on atrocities against women back home - is murdered, clues lead to an American military suspect and the team must determine their truth before another killing occurs.

Charlie helps the team solve how many shooters there were in a school massacre.

An ATF agent is found in her home, an apparent victim of suicide. Don, having been involved with her, asks Charlie to run algorithms to determine if she was likely suicidal, or she was murdered.

After an assailant opens fire in the FBI offices, Charlie does not want to return.

The Russian mob threatens Don and his family, however Charlie refuses to give up working the case.

The bodies of young Asian girls wash up on the beach, including one with bird flu. Amita gets a job offer.

Don's team investigates a rapist who's converted to a serial killer, as Charlie struggles with memories of his mother.