The Lightman Group looks into a murder case in which a woman with a multiple personalities disorder is involved and the group must decide whether she is a witness or the killer. Meanwhile, the U.S. government hires The Lightman Group to interrogate a potential Supreme Court nominee.

Zoe has the Lightman Group look into a college athlete accused of rape. Meanwhile, Foster and Loker head to a religious compound in order to determine whether or not it is actually a cult.

While in Mexico, Lightman and Emily work on a case involving a missing American woman. Back in the States, Foster looks into tainted blood in D.C. hospitals.

Eric Matheson, a man accused of killing is wife, is brought to the Lightman Group for questioning. Matheson goes to the extreme to convince everyone that he is innocent.

A face from Lightman’s past pulls him into a dangerous criminal conspiracy, testing his friendship and loyalty. Meanwhile, The Lightman Group investigates a high school student’s homicidal threats.

When a government witness is murdered, the FBI hires The Lightman Group to determine who leaked the witness’ whereabouts to the killers and to protect Agent Reynolds, the star witness in the case. When Reynolds refuses to testify in the case, Lightman and Foster learn he is hiding something in his past.

A troubled teenager believes he was abducted as a baby and turns to the Lightman Group to help him uncover the secrets of his past. Meanwhile, Loker investigates the origin of a deadly stampede that occurred at an electronics megastore the day after

Lightman visits Afghanistan on a mission to retrieve two captured Marines, with the help of an American expatriate.

A finalist of World Series of Poker is gone missing, so Lightman, Foster and Reynolds go to Vegas to investigate his disappearence. Meanwhile, Loker and Torres start bounding.

A disgruntled farmer parks his tractor, that’s packed with explosives, near the Treasury Department building, causing Lightman and his team to make som crucial life-or-death decisions. Meanwhile, a field trip for the third-grade gets stuck in the Lightman Group offices, and Loker is forced into playing babysitter, all during a political protest in Washington DC.

Lightman tries to prove that a brilliant and charming psychology graduate student is a psychopath; Torres and Loker investigate a UFO sighting.

After Lightman's former Pentagon colleague is killed in a car bomb, Lightman and Foster are forced to revisit a series of events from their past, including the therapy sessions that brought them together.

Lightman is called to testify in the trial of Clara, a sassy young widow accused of murdering her much older billionaire husband.

Torres's half-sister Ava (a resident at a juvenile detention facility) refuses to break the trust of a fellow inmate after the inmate was found killed. However, her refusal may have bad consequences for herself when her own life is put in jeopardy.

Lightman is hired by the D.C. Police to read the paralyzed victim of a horrifying shooting in a federal housing project. Meanwhile, Clara hires Cal to teach her how to read people; so she follows him everywhere.

Torres is forced to revisit her troubled past when her half-sister is incarcerated in a juvenile corrections facility.

After a young woman dies at a gubernatorial campaign rally in Virginia, The Lightman Group is hired to assess whether the case is a failed assassination attempt or a well-disguised murder plot.

Lightman risks being exposed as a gambler in an underground fight club when one of the fighters is found dead. Meanwhile, Foster's romance with Burns (guest star Max Martini) hits a snag when she uncovers a troubling secret.

Lightman and his ex-wife, Zoe (guest star Beals), witness the execution of a murderer they prosecuted 17 years ago and face the possibility that they sent the wrong man to his death

Foster's boyfriend (Dr. Dave Burns) gets into trouble and the only way Cal can save his life is to tell the truth.

A missing woman leads the Lightman group to discover criminal activity in the adult film industry.

When a journalist friend of Cal Lightman is murdered, the investigation tests his relationship with the FBI; Emily's interest in dating makes Cal uncomfortable.