The team is forced to relive the past when they receive a manifesto planning to copycat a previous mass shooting at an area high school with a higher body count.
20-Squad faces down a prison hostage situation, only to be thrown into deeper danger when a bomb explodes, freeing maximum-security prisoners from their cells, including someone with a personal grudge against Hondo.
When a spree of brutal stash house robberies spills into Los Angeles, the team joins with the sheriff's department's gang unit to unmask a violent crew who leaves no witness alive.
A blackout throws the city into chaos, forcing 20-Squad onto the streets for an emergency patrol day, which quickly escalates when Hondo and team uncover a terror threat.
SWAT faces their deadliest adversary yet when a violent cell of extremists looks to extract vengeance by blowing up half of Los Angeles, potentially killing thousands.
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; the SWAT division prepares to help Mumford mark a major career milestone.
