An abandoned oil well erupts and causes a massive sinkhole in downtown LA; Athena investigates a 30-year-old cold case involving a casino robbery; Buck fears his relationship with Taylor might be ending.

Bobby and the 118 race to save lives after an explosion rocks the hospital where Dr. David Hale is performing surgery; Michael makes a life-changing decision.

A man claims he was carjacked, shot and buried alive; a homeowner thinks her roommate is a ghost; Hen receives a visit from the past; Athena and family are concerned that Harry is still haunted by visions of Jeffrey.

Responding to a fire at a prison, Bobby and the 118 find themselves trapped in a deadly riot.

A man over-exerts himself exercising; a groundskeeper is cut by his chainsaw; an explosion occurs at a retirement community; May gets an emergency call from a suicidal teen.

The 118 springs into action when a citywide blackout and a record heat wave causes mayhem in Los Angeles; Chimney confides in Hen about Maddie's condition; Athena's worst nightmare comes true.

A series of ransomware threats leads to emergencies for the 118, including a helicopter crash at a hospital and an air traffic control tower system failure; the case of the realtor serial rapist goes to trial.