When a former Marine turned homeless is murdered, Kensi and Deeks go undercover for the investigation and find a link to the Mexican cartel.
Marco, Fausto, Obregon and Romina continue to make their escape through the mountains. Eleanor gets what she's wanted the most.
Marco tries to persuade Fausto to surrender while Sonya and Hank join forces with Frye and Adriana. Meanwhile, Linder wants Capitan Robles to pay for his past sins by taking matters into his own hands.moreless
While Marco meets with the Mexican Marines about capturing Fausto, Sonya interviews Eleanor and Frye and Adriana learn more about the extent of the CIA and DEA's involvement.
Sonya finds herself in a fight for her life as Marco desperately tries to save her. Betrayed by his organization, Fausto unleashes his revenge upon everyone meeting at Red Ridge.
Sonya visits a stranger from her past; Marco's tainted history is unearthed.
Sonya uncovers the truth behind Lisa's death. Meanwhile, Frye and Adriana make a dangerous discovery.
Frye makes a career move. Meanwhile, Eva takes matters into her own hands.
Marco confronts an old enemy. Later, Frye gets a proposition from the DEA.
Sonya and Marco make an unsettling discovery while tracking Eleanor. Later, Eva and Linder are reunited.
Sonya continues to investigate the death of an undercover DEA agent as Adriana and Daniel look into leads of their own. Meanwhile, Elenor shows her appreciation to those who help her.
Sonya meets a man connected to her past in the Season 2 premiere. Meanwhile, Marco questions his safety.
Investigating the death of a Wall Street trader leads Castle and Beckett to discover that the victim was an undercover informant for the U.S. Attorney’s office. To make matters worse, the U.S. attorney involved is Captain Gates' estranged sister.moreless
Sonya enlists Marcos' help in locating Eva. Charlotte firms up her business relationship with Fausto Galvan and in the process learns that her comings and goings are being monitored by persons unknown. Marco finds himself willing to "deal with the devil" in order to exact his revenge.moreless
Sonya uses Linder's latest problem to repair her relationship with Marco; Charlotte forms an unlikely alliance.
The case gets very personal when Hastings decides to make Marco's family his next victims. Graciela's confrontation with Charlotte regarding the trackers does not quite go as planned and Linder seeks Bob's guidance to help him in delivering some bad news.moreless
The more Sonya digs, the more she's convinced Childress is not their guy but it takes another killing during a library dedication before the true culprit is revealed. Charlotte's suspicions of Ray become valid but may also be too late and Linder's fragile psyche becomes too much for him to bear.moreless
Marco and Sonya's investigation leads them to Daniel Frye, a reporter whom the killer has apparently selected, first as an unwilling accomplice and then as his messenger and liaison. Learning about the shocking secret concealed on her property introduces Charlotte to some of her late husband's shady partners and dealings.moreless
An El Paso detective, Sonya Cross, and Marco Ruiz, a Chihuahua State Police Officer, are forced to work together when the body of a murdered judge is found on the bridge connecting El Paso and Juarez and is linked to a serial killer operating on both sides of the border.moreless