A locally born SWAT sergeant, former Marine Daniel “Hondo” Harrelson, is newly tasked to run a specialized tactical unit that is the last stop in law enforcement in Los Angeles.

Hondo and the SWAT team spread out across Los Angeles in pursuit of four escaped convicts, including a violent criminal Jessica helped bring to justice, before department rival Mumford and his team beat them to the collars. Also, Hondo’s new role as team leader is called into question when Street displays a flagrant disregard for SWAT protocol.

Hondo puts aside his misgivings about Jim Street's recklessness and allows the newbie to go undercover as a broker in a luxury car theft ring to bust a ruthless trafficker. Also, Hondo visits Raymont Harris, the teenager recently shot by a former member of the SWAT team, who is dealing with PTSD.

Hondo and the SWAT team are forced to work over their Christmas vacation when a drug cartel is out for blood after their cache of gold bars is stolen. Also, Jessica draws the attention of Michael Plank, president of the Police Commission, when she approaches him with her ideas on how to improve the SWAT division.

When a misconduct complaint filed against Hondo gets him taken off active duty, Deacon steps up to lead the team in finding a robbery crew that is hitting marijuana dispensaries. Also, when Tan notices a similarity between the current robberies and a case from his time with Hollywood LAPD, he asks for help from an informant with whom he has a complicated history.

As the SWAT team goes inside a prison riot to rescue civilian hostages, Hondo suspects the inmates have an ulterior motive behind the uprising. Also, when Deacon’s wife, Annie, stops by headquarters to celebrate Deacon’s 10th anniversary with the SWAT division, her visit takes an unexpected turn.

Hondo and the SWAT team join forces with the FBI on a manhunt to find members of a militia group planning a domestic terror attack by weaponizing cyanide. Also, as Jessica’s new police initiatives with Michael Plank, president of the police commission, move forward, she braces herself for the negative impact the plans could have on her relationships within the department.

Hondo and Jessica’s secret relationship comes to a crossroads when Michael Plank, the president of the police commission, discovers their affair. Also, when Hondo and the team assist with the federal investigation to bring in an undocumented fugitive, they find themselves at the center of a citywide immigration debate.

Hondo and the team go on the hunt for a serial killer who escaped justice two years prior by faking his death. Also, Hondo worries that Buck Spivey, the team’s former leader, is spiraling into depression in the aftermath of being fired from the department.

Hondo confronts his long-held resentment towards his ailing father, Daniel Harrelson, Sr., when he and his sister, Briana, try to convince their dad he’s no longer well enough to live alone. Also, when the SWAT team works as patrol officers for a day, Chris is partnered with Mumford, who intends to make her a surprising offer.

Jim Street debates whether or not his mother, Karen, should live with him upon her prison release after Hondo and Chris warn him against it. Also, Hondo and the team are assigned to protect Irina Zemanova, a high-profile Russian journalist visiting Los Angeles, from being assassinated.

Hondo and Deacon must apply all their SWAT training and skills to evade a gang of armed mercenaries hunting them in the Angeles Mountains following an ambush. Also, Chris oversteps in an attempt to help a female SWAT trainee she suspects isn’t being evaluated fairly.

A fake 911 call puts Hondo and the SWAT team on the hunt to stop a white supremacy group from executing bombing attacks on local communities. Also, Street’s relationship with his recently paroled mother, Karen, jeopardizes his career, and Jessica is thrown a curveball by her colleague, Michael Plank, president of the police commission. Hondo’s father, returns Daniel Harrelson, Sr. 1st.

The SWAT team engages in a standoff with human traffickers holding child hostages when a major earthquake hits Los Angeles during their operation and compromises the takedown. Hondo forms an unexpected personal connection with Deputy District Attorney Nia Wells. Jim Street has trouble adjusting to his new life as a patrol officer.

Hondo and Lina go undercover to infiltrate and take back a cruise ship that’s under siege by drug smugglers who will execute passengers if they detect police on board. Street enters the SWAT Training Academy and finds the competition fiercer than he expected.

When the SWAT team is called in to work on their day off to end a hostage situation, they discover one of the captives is a wanted felon. When Hondo saves his sister after she's been roofied at a nightclub, he uses his day off to hunt a serial rapist.

Hondo reunites with an old flame, FBI Special Agent Elle Trask, when the SWAT team works with the FBI to bring in a separatist group with weapons-grade plutonium. Also, the SWAT team worries they will lose an annual law enforcement charity competition to the Los Angeles Fire Department.

The SWAT team pursues a group of unknown assailants responsible for a patrol officer’s death before tension in the city between the police and the community explodes. Also, as Chris reels from the revelation that she knew the patrol officer who was killed, Deacon and his wife, Annie, prepare to welcome their newest child.

The SWAT team tries to zero in on the next target of a carjacking ring that’s using deadly force to boost luxury vehicles all over Los Angeles. Also, Hondo takes a big step to help his childhood friend’s incarcerated son, Darryl, and SWAT team leader Mumford weighs a major decision.

The abduction of Luca and Street’s neighbor sends the SWAT team in pursuit of a home invasion crew targeting domestic workers to gain entry into upscale homes. Also, the SWAT division prepares to help Mumford mark a major career milestone.

Deacon’s family gets caught in the crosshairs of a drug cartel when he and the SWAT team aim to bring down its leader, a former foreign rebel force leader running drugs in plain sight via a local flower market. Also, Hondo receives troubling news regarding his father, and Tan is forced to go before an internal review board due to his girlfriend’s indiscretion.

The Harrelsons engage in a tense family reunion when Hondo’s older sister, Winnie, begrudgingly arrives in Los Angeles to see their sick father for the first time in decades. Also, the SWAT team searches for an abducted Middle Eastern human rights activist; Luca’s food truck business hits a snag; and Street worries that dating Captain Hick’s daughter, Molly, will negatively impact his career.

The SWAT team searches for thieves who are on the run with a high-tech thermal lance that can cut through almost anything. To find the thieves, SWAT works to identify their target. Also, Chris confronts an imbalance in her relationship with Kira and Ty.

The SWAT team engages in tense negotiations with a family that takes a local officer hostage when they’re evicted from their home due to eminent domain. Also, Hondo reflects on his personal life choices as he helps his father through a medical crisis and Chris’ relationship with Kira and Ty reaches a critical juncture.

The SWAT team must protect a hotel full of civilians after a joint task force mission with the LAPD Gang Division goes wrong, and the city’s most dangerous gang leaders scatter across the building to find an escape. Also, Luca’s efforts to coordinate the team’s mission are complicated when his brother, Terry, a freelance stringer reporter, crosses police lines to shoot footage.

Chris brings the SWAT team into her personal mission to save a teenage girl from a charismatic, predatory religious leader using his church for illicit gain. Also, Hondo receives troubling news about Darryl related to Leroy, Darryl's father, being released from prison, and Tan's wedding planning hits a snag.

The SWAT team goes on the hunt for a sniper who is targeting the Los Angeles Fire Department by setting fires around the city to lure in unsuspecting engine companies. Also, the rivalry between Chris, Street and Tan ratchets up when Tan finds out there’s an internal betting pool on which of them will win the SWAT leadership competition. And, Street and Molly’s relationship is strained by his complicated history with his imprisoned mother.

A tragic mission leads each member of the SWAT team to contend with their emotional distress in varied ways.

As the team works to stop a violent attack on the city, they're forced to confront the group responsible for the death of a team member. Hondo and Leroy disagree on how to handle a challenge to Darryl's fledgling business.

Still in Mexico, Hondo teams up with a local cop for a dangerous rescue mission, only to find himself with a target on his back. Also, back in Los Angeles, Hicks considers disbanding the team for good.

The team participates in a joint task force with the FBI when a car bombing has ties to a terrorist group planning an attack in Los Angeles; a tragedy from Deacon’s past gives insight into the origins of his faith.

SWAT teams with Major Crimes for a high-stakes mission to extract an undercover officer from a dangerous crime ring.

Hondo and Hicks desperately search for Powell, who's gone missing in Mexico City along with a thermobaric bomb capable of killing thousands. Deacon's pride gets injured in a boxing match with Rocker.

When a female robbery crew "honeytraps" and kills several rich VIPs, Hondo and 20-Squad are called in to assist FBI Agent Jackie Vasquez in capturing the dangerous fugitives before the death toll rises. Commander Hicks is shocked when his new love, Maggie, abruptly ends their relationship without rhyme or reason. With help from Deacon and Dr. Wendy, Hicks makes an important decision about his romantic future.