The NCIS team partners with several federal agencies to track a sniper who is targeting crowded events in the city. Also, FBI Special Agent Tammy Gregorio arrives to investigate Pride and his team.

Pride faces further backlash from the FBI when he helps former Navy Intelligence Analyst Elvis Bertrand, who is the lead suspect in a multiple homicide case.

After a decorated petty officer is found dead inside a sports arena, evidence leads Pride and the NCIS team to a kidnapping case of a petty officer who was last seen in Mexico.

Pride and his team investigate the crash of a private plane in a bayou, while LaSalle and Percy interview potential replacements for Brody.

Pride takes temporary custody of a 9-year-old boy who's the sole witness to the murder of his aunt - a member of the United States Navy Band.

When the Coast Guard boards a yacht that is in an area that is used by smugglers, they find the Captain with the crew's waiter who is dead. They try to get him but he resists and kills him. The Coast Guard calls Pride because the yacht belongs to Javier Garcia. Pride thinks Garcia was smuggling something. He calls the FBI to tell them about it and sends LaSalle to help Gregorio. Pride discovers one of the passengers is someone he knows and that she's engaged to Garcia. Instead of arresting the men who took off the yacht what they were bringing in Gregorio decides to follow them instead if arresting them but things don't work out as planned. Isler wants Pride's friend to help them but Pride says it's too dangerous but she agrees to do it.

Sebastian is sent undercover and Patton exercises his former gambling skills, as Pride and the team attempt a dangerous operation to trap Garcia.

Unable to trust anyone in New Orleans, the NCIS team calls in FBI Assistant Director Isler (Derek Webster) to help expose and stop the sinister scheme Mayor Hamilton (Steven Weber) has planned for the residents of Clearwater, on the third season finale.

Pride and the Gang team with FBI to find a Russian with important info on sleepers in the USA.

Sebastian is placed on administrative leave when the FBI questions his response in a foot chase to apprehend a high value fugitive.

After Rita Deveraux tells Pride that Douglas Hamilton is about to make a deal to get out of prison, Pride and the team rehash the Clearwater case in hopes of locating his mystery partner and spoiling his bargaining chip. Stacy Keach guest stars.

Sebastian receives a plea for help from his high school friend Adrian Conner after her business partner is killed at the Crescent City Gaming Convention. Also, FBI Special Agent Raymond Isler believes Adrian is a hacker the Cyber Crimes division has been tracking for years.

Pride helps FBI Special Agent Isler with an off-the-books opioid theft investigation.

After a reshuffling of assignments, Pride returns to the New Orleans office during the investigation of a missing petty officer.

The team splits to investigate an Apollyon plot. Pride goes to assist a fallen friend whilst the Team investigates a leak.

After tracking Apollyon, a deadly underground spy network, to war-torn South Ossetia, Pride is separated from the team and faces grave danger. Also, in order to save Pride, the NCIS team must locate a mole who continues to feed information to Apollyon.

The team uncovers a sinister plot by a private detention center contracted by the government to house undocumented immigrants; Lasalle and Sebastian travel to Alabama to search for Lasalle's missing brother.