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.

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.

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 works together with former member, Jim Street to find a woman and her son who are running from an international drug cartel. Hondo makes a distressing discovery about his incarcerated friend’s teen son. Luca mulls over a government program that allows officers to buy homes in the at-risk neighborhoods they police.

The SWAT team goes in pursuit again of the militant group The Emancipators, when the criminals hold a live stream kangaroo court to publicly execute city politicians. Also, Hondo fights to lift Darryl’s spirits; Deacon feels unworthy as he prepares to receive one of the LAPD’s highest honors; and Street catches a break in the search for his missing parolee mother.

Street reconnects with his estranged foster brother, Nate, to help a joint investigation between SWAT and the Long Beach Police Department when criminals steal a mass arsenal of LAPD assault rifles. Also, Hondo finds himself at odds with his father over the elder man’s declining health, and Luca is overwhelmed when the entire team reconsiders becoming investors in his food truck,

Hondo, his father Daniel Sr. and his teen charge Darryl confront the history of racial tension in Los Angeles between law enforcement and the Black community, through flashbacks to the city in 1992 following the Rodney King verdict. Also, the SWAT team pursues El Diablo’s scattered drug cartel hiding in the city and a Jihadist group detonating bombs in coordinated attacks,

Hondo is conflicted when Leroy, his incarcerated childhood friend and Darryl's father, asks him to speak on his behalf at a parole hearing. Also, SWAT helps the FBI track down a mob informant on the run from the crime family he is meant to testify against, and the team dynamic becomes complicated when Street and Tan sign up for a leadership competition Chris has been training months for.